Success: APP sensor replacement cured P2138 and non-smooth accelerator response
05-19-2011, 01:02 PM
#1
Advanced
Thread Starter
Success: APP sensor replacement cured P2138 and non-smooth accelerator response
I have a DIY success story to share. There seems to be a lot of discussion about this in the 3rd gen TL forums, but the issue applies to the TSX too and I haven't found much discussion about this in reference to TSXes.
A few weeks ago I started feeling like the transmission in my 04 5AT TSX (99k miles) was acting a little weird. It was shifting a little hard and also seemed to be shifting back and forth a little too often in lower gears. To get a better handle on it, I put it in sportshift (M) mode and drove a few miles, trying to get a better feel for what exactly it was doing weirdly. As I was taking off from a stop at a light, there was a big clunk, the check-engine light, VSA, and ! triangle lights came on, the sportshift would not let me change gears, and the gear indicator was blank even in M mode. The car also was accelerating very slowly like there was no power. At first I thought it was stuck in a higher gear. I drove it home (1/2 mile) and freaked out, thinking the tranny had just bit the dust. I let it cool down for a couple of hrs and then drove around the block slowly. the CEL was still on, but the other two lights were off, and it seemed to be shifting gears ok.
I found a neighbor with a code scanner and discovered it was throwing a P2138 which is "Accelerator Pedal Position (APP) Sensor 1/2 (Throttle Position Sensor D/E) Incorrect Voltage Correlation" After doing a lot of reading and research, I came to learn that the TSX drive by wire system consists of a cable that goes from the accelerator pedal, through the firewall, and into an APP sensor module in the engine compartment. That module detects the position of the pedal cable and sends the current position to the ECU (I'm assuming via an analog voltage signal driven by a pot in the sensor in a voltage divider config, but I haven't done any measurements to confirm). I believe the sensor module actually has two sensors and sends both values to the ECU. If the ECU determines the two sensors differ too much, it throws the P2138 error and runs in a "gimp mode" of sorts where the engine is not allowed to exceed a certain rpm or power in order to protect the engine. Restarting the engine (rebooting the ECU) seems to reset things and lets the engine run normally again.
I drove on it for about a week afterward, but payed close attention to the accelerator pedal response. Thinking back, I realized I had noticed a gradual deterioration over time of the smoothness and responsiveness of the pedal in the low range. In fact, I noticed that it was getting pretty hard to start out smoothly from a stop. Also, I discovered that it was hard to maintain a constant RPM in certain pedal positions near the low end. I found one post on a TL forum (the TL uses the same APP sensor as the TSX in similar model years) of someone watching the butterfly valve in his throttle body moving very erratically when the APP was anywhere in the low range. That description really was matching what I was feeling with how the engine was responding. I also had some instances where the car had a hard time even maintaining a constant idle rpm when the car was not moving.
tl;dr, I know. Long story short, I finally ordered a new APP sensor module, 37971-RBB-003, from hondapartsunlimited.com for about 140 shipped and installed it in about 15-30 mins. I'm not one to generally work under the hood; about the most complex thing I've done in the engine compartment of this car is change the O ring on the power steering pump inlet (best 60 cents I ever spent! It totally solved the pump cavitation whine when cold). But swapping the APP sensor was pretty straightforward and not difficult at all. Tools needed: 10mm socket with extension and 12mm open end wrench.
The difference is night and day (ok, late evening and day). After driving for about 45 minutes on the new sensor, I can tell that the problem was worse than I realized. I can now start out smoothly from a stop without the car lurching forward! And the engine seems to run smoother at lower rpms. I also haven't noticed any of the odd transmission behaviors that I had noticed previously.
A few weeks ago I started feeling like the transmission in my 04 5AT TSX (99k miles) was acting a little weird. It was shifting a little hard and also seemed to be shifting back and forth a little too often in lower gears. To get a better handle on it, I put it in sportshift (M) mode and drove a few miles, trying to get a better feel for what exactly it was doing weirdly. As I was taking off from a stop at a light, there was a big clunk, the check-engine light, VSA, and ! triangle lights came on, the sportshift would not let me change gears, and the gear indicator was blank even in M mode. The car also was accelerating very slowly like there was no power. At first I thought it was stuck in a higher gear. I drove it home (1/2 mile) and freaked out, thinking the tranny had just bit the dust. I let it cool down for a couple of hrs and then drove around the block slowly. the CEL was still on, but the other two lights were off, and it seemed to be shifting gears ok.
I found a neighbor with a code scanner and discovered it was throwing a P2138 which is "Accelerator Pedal Position (APP) Sensor 1/2 (Throttle Position Sensor D/E) Incorrect Voltage Correlation" After doing a lot of reading and research, I came to learn that the TSX drive by wire system consists of a cable that goes from the accelerator pedal, through the firewall, and into an APP sensor module in the engine compartment. That module detects the position of the pedal cable and sends the current position to the ECU (I'm assuming via an analog voltage signal driven by a pot in the sensor in a voltage divider config, but I haven't done any measurements to confirm). I believe the sensor module actually has two sensors and sends both values to the ECU. If the ECU determines the two sensors differ too much, it throws the P2138 error and runs in a "gimp mode" of sorts where the engine is not allowed to exceed a certain rpm or power in order to protect the engine. Restarting the engine (rebooting the ECU) seems to reset things and lets the engine run normally again.
I drove on it for about a week afterward, but payed close attention to the accelerator pedal response. Thinking back, I realized I had noticed a gradual deterioration over time of the smoothness and responsiveness of the pedal in the low range. In fact, I noticed that it was getting pretty hard to start out smoothly from a stop. Also, I discovered that it was hard to maintain a constant RPM in certain pedal positions near the low end. I found one post on a TL forum (the TL uses the same APP sensor as the TSX in similar model years) of someone watching the butterfly valve in his throttle body moving very erratically when the APP was anywhere in the low range. That description really was matching what I was feeling with how the engine was responding. I also had some instances where the car had a hard time even maintaining a constant idle rpm when the car was not moving.
tl;dr, I know. Long story short, I finally ordered a new APP sensor module, 37971-RBB-003, from hondapartsunlimited.com for about 140 shipped and installed it in about 15-30 mins. I'm not one to generally work under the hood; about the most complex thing I've done in the engine compartment of this car is change the O ring on the power steering pump inlet (best 60 cents I ever spent! It totally solved the pump cavitation whine when cold). But swapping the APP sensor was pretty straightforward and not difficult at all. Tools needed: 10mm socket with extension and 12mm open end wrench.
The difference is night and day (ok, late evening and day). After driving for about 45 minutes on the new sensor, I can tell that the problem was worse than I realized. I can now start out smoothly from a stop without the car lurching forward! And the engine seems to run smoother at lower rpms. I also haven't noticed any of the odd transmission behaviors that I had noticed previously.
The following 6 users liked this post by jsharper:
cor6bro (06-06-2011),
Lone Starr (08-20-2014),
musicosolo (06-11-2012),
redbox75 (07-16-2011),
tjessica (08-28-2013),
and 1 others liked this post.
05-23-2011, 12:45 PM
#3
Instructor
Glad to hear!
I have a similar problem that I believe i've isolated to the APP sensor as well.. I posted a thread a while ago.. good to know that it's an easy remove and replace job..
basic problem is every once in a while, I'll experience a slight hesitation while cruising at a constant speed (at low throttle, and never happens when I set the cruise control... i'm thinking the cruise bypasses the pedal sensor?)..
problem comes and goes so I haven't made the repair..
I have a similar problem that I believe i've isolated to the APP sensor as well.. I posted a thread a while ago.. good to know that it's an easy remove and replace job..
basic problem is every once in a while, I'll experience a slight hesitation while cruising at a constant speed (at low throttle, and never happens when I set the cruise control... i'm thinking the cruise bypasses the pedal sensor?)..
problem comes and goes so I haven't made the repair..
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musicosolo (06-11-2012)
06-06-2011, 11:03 PM
#4
Advanced
I have a DIY success story to share. There seems to be a lot of discussion about this in the 3rd gen TL forums, but the issue applies to the TSX too and I haven't found much discussion about this in reference to TSXes.
A few weeks ago I started feeling like the transmission in my 04 5AT TSX (99k miles) was acting a little weird. It was shifting a little hard and also seemed to be shifting back and forth a little too often in lower gears. To get a better handle on it, I put it in sportshift (M) mode and drove a few miles, trying to get a better feel for what exactly it was doing weirdly. As I was taking off from a stop at a light, there was a big clunk, the check-engine light, VSA, and ! triangle lights came on, the sportshift would not let me change gears, and the gear indicator was blank even in M mode. The car also was accelerating very slowly like there was no power. At first I thought it was stuck in a higher gear. I drove it home (1/2 mile) and freaked out, thinking the tranny had just bit the dust. I let it cool down for a couple of hrs and then drove around the block slowly. the CEL was still on, but the other two lights were off, and it seemed to be shifting gears ok.
I found a neighbor with a code scanner and discovered it was throwing a P2138 which is "Accelerator Pedal Position (APP) Sensor 1/2 (Throttle Position Sensor D/E) Incorrect Voltage Correlation" After doing a lot of reading and research, I came to learn that the TSX drive by wire system consists of a cable that goes from the accelerator pedal, through the firewall, and into an APP sensor module in the engine compartment. That module detects the position of the pedal cable and sends the current position to the ECU (I'm assuming via an analog voltage signal driven by a pot in the sensor in a voltage divider config, but I haven't done any measurements to confirm). I believe the sensor module actually has two sensors and sends both values to the ECU. If the ECU determines the two sensors differ too much, it throws the P2138 error and runs in a "gimp mode" of sorts where the engine is not allowed to exceed a certain rpm or power in order to protect the engine. Restarting the engine (rebooting the ECU) seems to reset things and lets the engine run normally again.
I drove on it for about a week afterward, but payed close attention to the accelerator pedal response. Thinking back, I realized I had noticed a gradual deterioration over time of the smoothness and responsiveness of the pedal in the low range. In fact, I noticed that it was getting pretty hard to start out smoothly from a stop. Also, I discovered that it was hard to maintain a constant RPM in certain pedal positions near the low end. I found one post on a TL forum (the TL uses the same APP sensor as the TSX in similar model years) of someone watching the butterfly valve in his throttle body moving very erratically when the APP was anywhere in the low range. That description really was matching what I was feeling with how the engine was responding. I also had some instances where the car had a hard time even maintaining a constant idle rpm when the car was not moving.
tl;dr, I know. Long story short, I finally ordered a new APP sensor module, 37971-RBB-003, from hondapartsunlimited.com for about 140 shipped and installed it in about 15-30 mins. I'm not one to generally work under the hood; about the most complex thing I've done in the engine compartment of this car is change the O ring on the power steering pump inlet (best 60 cents I ever spent! It totally solved the pump cavitation whine when cold). But swapping the APP sensor was pretty straightforward and not difficult at all. Tools needed: 10mm socket with extension and 12mm open end wrench.
The difference is night and day (ok, late evening and day). After driving for about 45 minutes on the new sensor, I can tell that the problem was worse than I realized. I can now start out smoothly from a stop without the car lurching forward! And the engine seems to run smoother at lower rpms. I also haven't noticed any of the odd transmission behaviors that I had noticed previously.
A few weeks ago I started feeling like the transmission in my 04 5AT TSX (99k miles) was acting a little weird. It was shifting a little hard and also seemed to be shifting back and forth a little too often in lower gears. To get a better handle on it, I put it in sportshift (M) mode and drove a few miles, trying to get a better feel for what exactly it was doing weirdly. As I was taking off from a stop at a light, there was a big clunk, the check-engine light, VSA, and ! triangle lights came on, the sportshift would not let me change gears, and the gear indicator was blank even in M mode. The car also was accelerating very slowly like there was no power. At first I thought it was stuck in a higher gear. I drove it home (1/2 mile) and freaked out, thinking the tranny had just bit the dust. I let it cool down for a couple of hrs and then drove around the block slowly. the CEL was still on, but the other two lights were off, and it seemed to be shifting gears ok.
I found a neighbor with a code scanner and discovered it was throwing a P2138 which is "Accelerator Pedal Position (APP) Sensor 1/2 (Throttle Position Sensor D/E) Incorrect Voltage Correlation" After doing a lot of reading and research, I came to learn that the TSX drive by wire system consists of a cable that goes from the accelerator pedal, through the firewall, and into an APP sensor module in the engine compartment. That module detects the position of the pedal cable and sends the current position to the ECU (I'm assuming via an analog voltage signal driven by a pot in the sensor in a voltage divider config, but I haven't done any measurements to confirm). I believe the sensor module actually has two sensors and sends both values to the ECU. If the ECU determines the two sensors differ too much, it throws the P2138 error and runs in a "gimp mode" of sorts where the engine is not allowed to exceed a certain rpm or power in order to protect the engine. Restarting the engine (rebooting the ECU) seems to reset things and lets the engine run normally again.
I drove on it for about a week afterward, but payed close attention to the accelerator pedal response. Thinking back, I realized I had noticed a gradual deterioration over time of the smoothness and responsiveness of the pedal in the low range. In fact, I noticed that it was getting pretty hard to start out smoothly from a stop. Also, I discovered that it was hard to maintain a constant RPM in certain pedal positions near the low end. I found one post on a TL forum (the TL uses the same APP sensor as the TSX in similar model years) of someone watching the butterfly valve in his throttle body moving very erratically when the APP was anywhere in the low range. That description really was matching what I was feeling with how the engine was responding. I also had some instances where the car had a hard time even maintaining a constant idle rpm when the car was not moving.
tl;dr, I know. Long story short, I finally ordered a new APP sensor module, 37971-RBB-003, from hondapartsunlimited.com for about 140 shipped and installed it in about 15-30 mins. I'm not one to generally work under the hood; about the most complex thing I've done in the engine compartment of this car is change the O ring on the power steering pump inlet (best 60 cents I ever spent! It totally solved the pump cavitation whine when cold). But swapping the APP sensor was pretty straightforward and not difficult at all. Tools needed: 10mm socket with extension and 12mm open end wrench.
The difference is night and day (ok, late evening and day). After driving for about 45 minutes on the new sensor, I can tell that the problem was worse than I realized. I can now start out smoothly from a stop without the car lurching forward! And the engine seems to run smoother at lower rpms. I also haven't noticed any of the odd transmission behaviors that I had noticed previously.
Repair wise, it’s been a crazy couple of months. One water pump replacement (dealership), several trips to my not-so-local mechanic in order to sort out several issues with the clutch hydraulics. All told, several hundred dollars worth of repairs.
Probably saved a hundred or more by doing this repair myself. It was a little challenging at first to get to all of the 10 mm bolts on the underside of the mounting bracket, but eventually I was able to get it done in about an hour and change – including a trip to Home Depot to get a standard socket set for my 1/4 inch drive ratchet. My deep socket set didn’t provide for enough clearance to use the ratchet.
In addition, I kinda guessed on the nut position for the accelerator cable. On my car, there is a white stripe on one of the adjustment nuts. I visually realigned it roughly to where it was prior to disassembly (facing up). There is probably a specification on how to properly adjust it, however, the assembly seems to be fairly forgiving in its re-installation. Accelerator dead band seems roughly the same as what it was before the repair.
The only other thing I need to do is get a new rubber breather joint that ripped off from the intake (not sure when and how that happened), but it’s only a 3-dollar part.
My 2004 6MT has about 147k miles on the odo. Still love driving it though.
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musicosolo (06-11-2012)
06-07-2011, 07:48 AM
#5
Instructor
cor6bro - what was your car doing prior to the app sensor replacement? I have still yet to replace mine.. even though it's showing the early signs of failure..
my '04 6mt also has 147k btw
my '04 6mt also has 147k btw
06-08-2011, 05:34 PM
#6
I have a DIY success story to share. There seems to be a lot of discussion about this in the 3rd gen TL forums, but the issue applies to the TSX too and I haven't found much discussion about this in reference to TSXes.
A few weeks ago I started feeling like the transmission in my 04 5AT TSX (99k miles) was acting a little weird. It was shifting a little hard and also seemed to be shifting back and forth a little too often in lower gears. To get a better handle on it, I put it in sportshift (M) mode and drove a few miles, trying to get a better feel for what exactly it was doing weirdly. As I was taking off from a stop at a light, there was a big clunk, the check-engine light, VSA, and ! triangle lights came on, the sportshift would not let me change gears, and the gear indicator was blank even in M mode. The car also was accelerating very slowly like there was no power. At first I thought it was stuck in a higher gear. I drove it home (1/2 mile) and freaked out, thinking the tranny had just bit the dust. I let it cool down for a couple of hrs and then drove around the block slowly. the CEL was still on, but the other two lights were off, and it seemed to be shifting gears ok.
I found a neighbor with a code scanner and discovered it was throwing a P2138 which is "Accelerator Pedal Position (APP) Sensor 1/2 (Throttle Position Sensor D/E) Incorrect Voltage Correlation" After doing a lot of reading and research, I came to learn that the TSX drive by wire system consists of a cable that goes from the accelerator pedal, through the firewall, and into an APP sensor module in the engine compartment. That module detects the position of the pedal cable and sends the current position to the ECU (I'm assuming via an analog voltage signal driven by a pot in the sensor in a voltage divider config, but I haven't done any measurements to confirm). I believe the sensor module actually has two sensors and sends both values to the ECU. If the ECU determines the two sensors differ too much, it throws the P2138 error and runs in a "gimp mode" of sorts where the engine is not allowed to exceed a certain rpm or power in order to protect the engine. Restarting the engine (rebooting the ECU) seems to reset things and lets the engine run normally again.
I drove on it for about a week afterward, but payed close attention to the accelerator pedal response. Thinking back, I realized I had noticed a gradual deterioration over time of the smoothness and responsiveness of the pedal in the low range. In fact, I noticed that it was getting pretty hard to start out smoothly from a stop. Also, I discovered that it was hard to maintain a constant RPM in certain pedal positions near the low end. I found one post on a TL forum (the TL uses the same APP sensor as the TSX in similar model years) of someone watching the butterfly valve in his throttle body moving very erratically when the APP was anywhere in the low range. That description really was matching what I was feeling with how the engine was responding. I also had some instances where the car had a hard time even maintaining a constant idle rpm when the car was not moving.
tl;dr, I know. Long story short, I finally ordered a new APP sensor module, 37971-RBB-003, from hondapartsunlimited.com for about 140 shipped and installed it in about 15-30 mins. I'm not one to generally work under the hood; about the most complex thing I've done in the engine compartment of this car is change the O ring on the power steering pump inlet (best 60 cents I ever spent! It totally solved the pump cavitation whine when cold). But swapping the APP sensor was pretty straightforward and not difficult at all. Tools needed: 10mm socket with extension and 12mm open end wrench.
The difference is night and day (ok, late evening and day). After driving for about 45 minutes on the new sensor, I can tell that the problem was worse than I realized. I can now start out smoothly from a stop without the car lurching forward! And the engine seems to run smoother at lower rpms. I also haven't noticed any of the odd transmission behaviors that I had noticed previously.
A few weeks ago I started feeling like the transmission in my 04 5AT TSX (99k miles) was acting a little weird. It was shifting a little hard and also seemed to be shifting back and forth a little too often in lower gears. To get a better handle on it, I put it in sportshift (M) mode and drove a few miles, trying to get a better feel for what exactly it was doing weirdly. As I was taking off from a stop at a light, there was a big clunk, the check-engine light, VSA, and ! triangle lights came on, the sportshift would not let me change gears, and the gear indicator was blank even in M mode. The car also was accelerating very slowly like there was no power. At first I thought it was stuck in a higher gear. I drove it home (1/2 mile) and freaked out, thinking the tranny had just bit the dust. I let it cool down for a couple of hrs and then drove around the block slowly. the CEL was still on, but the other two lights were off, and it seemed to be shifting gears ok.
I found a neighbor with a code scanner and discovered it was throwing a P2138 which is "Accelerator Pedal Position (APP) Sensor 1/2 (Throttle Position Sensor D/E) Incorrect Voltage Correlation" After doing a lot of reading and research, I came to learn that the TSX drive by wire system consists of a cable that goes from the accelerator pedal, through the firewall, and into an APP sensor module in the engine compartment. That module detects the position of the pedal cable and sends the current position to the ECU (I'm assuming via an analog voltage signal driven by a pot in the sensor in a voltage divider config, but I haven't done any measurements to confirm). I believe the sensor module actually has two sensors and sends both values to the ECU. If the ECU determines the two sensors differ too much, it throws the P2138 error and runs in a "gimp mode" of sorts where the engine is not allowed to exceed a certain rpm or power in order to protect the engine. Restarting the engine (rebooting the ECU) seems to reset things and lets the engine run normally again.
I drove on it for about a week afterward, but payed close attention to the accelerator pedal response. Thinking back, I realized I had noticed a gradual deterioration over time of the smoothness and responsiveness of the pedal in the low range. In fact, I noticed that it was getting pretty hard to start out smoothly from a stop. Also, I discovered that it was hard to maintain a constant RPM in certain pedal positions near the low end. I found one post on a TL forum (the TL uses the same APP sensor as the TSX in similar model years) of someone watching the butterfly valve in his throttle body moving very erratically when the APP was anywhere in the low range. That description really was matching what I was feeling with how the engine was responding. I also had some instances where the car had a hard time even maintaining a constant idle rpm when the car was not moving.
tl;dr, I know. Long story short, I finally ordered a new APP sensor module, 37971-RBB-003, from hondapartsunlimited.com for about 140 shipped and installed it in about 15-30 mins. I'm not one to generally work under the hood; about the most complex thing I've done in the engine compartment of this car is change the O ring on the power steering pump inlet (best 60 cents I ever spent! It totally solved the pump cavitation whine when cold). But swapping the APP sensor was pretty straightforward and not difficult at all. Tools needed: 10mm socket with extension and 12mm open end wrench.
The difference is night and day (ok, late evening and day). After driving for about 45 minutes on the new sensor, I can tell that the problem was worse than I realized. I can now start out smoothly from a stop without the car lurching forward! And the engine seems to run smoother at lower rpms. I also haven't noticed any of the odd transmission behaviors that I had noticed previously.
jsharper:
When you say it was "hard to start out smoothly from a stop", do you mean from both the regular automatic mode and sportsshift mode or just one of them?
06-08-2011, 10:56 PM
#7
Advanced
I didn’t notice much lag during hard acceleration or in city driving. However, since I’ve swapped out the sensor, the car drives much smoother around town and on the highway.
It was when I read jsharper’s post that I decided to test if this issue was apparent when cruise control was engaged. It wasn’t. Thus, I purchased the part and installed it myself.
The only caveat I would add is that I had multiple issues with the car at the time. One was an issue with clutch hydraulics and a marginal clutch engagement point due to a previous repair for a faulty master cylinder: Two, a busted rubber connector between the crank case breather and intake manifold. As a result, I can’t qualify how much drivability was affected in local driving.
My wild guess is that this sensor is bound to “die” eventually. It’s mounted on rubber isolators and because it’s electronic, it’s probably heat and vibration sensitive. I’m running an aftermarket header (without a heat shield). So it gets fairly hot in the location where this thing is mounted.
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06-14-2011, 11:51 AM
#8
Instructor
Sounds like my problem exactly with the "dragging" while cruising.. looks like i'm due.. but now that it's warmer out here, i've been able to ride my motorcycle to work.. so the tsx hasn't left the garage much
06-16-2011, 07:53 PM
#9
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thank you!
I was having same lights coming on and replaced the app. It has made an instant improvement in my car response and idle. I'm just waiting to see if any of the old symptoms come back. At 181k on my 04 at tsx, the app part was almost equivalent to hondata reflash. How the car should be in the first place.
06-27-2011, 12:21 PM
#11
Instructor
I can take a pic for you today as I'm going to replace mine after I get out of work... but if you want to look now, it's attached to the firewall, in the engine compartment.. passenger side.. there's a cable (from the accelerator pedal) running into the small black assembly..
07-08-2011, 02:33 AM
#12
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app sensor replacement p2138
I had the same issue a last year. Before having the sensor pedal replaced, my mechanic offered to pull out and clean my existing sensor. Havent had a problem since.
07-16-2011, 09:37 PM
#14
Current '06 TSX Owner
I have an '06 TSX MT with 82K miles that's showing signs of this too (same P2138 code, similar hesitation being observed even when applying constant pressure on the throttle, check engine and VSA lights appearing occasionally).
I ordered a new APP sensor and I also wanted to ask -- does anyone have the replacement instructions for this?
I wasn't able to find anything through a search -- just the blowup diagram of each part of the accelerator sensor assembly.
I ordered a new APP sensor and I also wanted to ask -- does anyone have the replacement instructions for this?
I wasn't able to find anything through a search -- just the blowup diagram of each part of the accelerator sensor assembly.
07-16-2011, 11:15 PM
#15
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I did mine last week. all you need is a 10 mm socket and an extension and it's real self explanatory. I did mine in about 20 minutes and I am very un mechanic savvy...
07-21-2011, 12:39 AM
#16
3rd Gear
Thank you! Thank you! Thank you!
Thanks so much jsharper and everyone else. I'm having the same symptoms with my 2007 Acura TL Type-S (5-speed auto):
- Less-than-smooth acceleration
- Engine light comes on
- On one occasion, car would not accelerate past 20 mph
07-25-2011, 12:37 AM
#17
Current '06 TSX Owner
I just swapped my APP sensor and my previously reported problems appear to have gone away. Having never worked under the hood of my car before, I was quite surprised over how easy it was. Thanks to everyone on this thread for the helpful info!
10-02-2011, 10:45 PM
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06 5at tsx 56,xxx miles. Car bought in Feb'07
Same problem with the CEL's, Car is putting out codes p2138 and p2122.
P2122 - APP Sensor 1 Low Input
Probable Causes:
1 - Failed APP Sensor 1
2 - Open or short circuit condition
3 - Poor electrical connection
----------------------------
P2138 - APP Sensor Performance Condition Fault
Probable Causes:
1 - Failed APP Sensor
2 - Open or short circuit condition
3 - Poor electrical connection
Spoke to a honda tech and he said it was most likely the APP sensor.
I replaced it but no luck. Problem is still existing. And it's actually gotten worse.
To give some insight on when the problem started happening... My car sat in my driveway for about a month, when i tried to start it the battery had died and wouldn't hold it's charge so i replaced the battery. After driving about 25 miles over the next 2 days, it came on after i parked it for work. Code went away and has been coming back every once in a while for the past month or so but would go away after restarting the car.
But now the car is pretty much bricked.
Symptoms:
1) High idle on startup.
2) Slow throttle, the car seems to be in limp mode and it accelerates really slow.
3) It allows me to go into second gear but won't shift above that.
4) Shift from 1st to 2nd gear is really rough.
Any input would be greatly appreciated.
Same problem with the CEL's, Car is putting out codes p2138 and p2122.
P2122 - APP Sensor 1 Low Input
Probable Causes:
1 - Failed APP Sensor 1
2 - Open or short circuit condition
3 - Poor electrical connection
----------------------------
P2138 - APP Sensor Performance Condition Fault
Probable Causes:
1 - Failed APP Sensor
2 - Open or short circuit condition
3 - Poor electrical connection
Spoke to a honda tech and he said it was most likely the APP sensor.
I replaced it but no luck. Problem is still existing. And it's actually gotten worse.
To give some insight on when the problem started happening... My car sat in my driveway for about a month, when i tried to start it the battery had died and wouldn't hold it's charge so i replaced the battery. After driving about 25 miles over the next 2 days, it came on after i parked it for work. Code went away and has been coming back every once in a while for the past month or so but would go away after restarting the car.
But now the car is pretty much bricked.
Symptoms:
1) High idle on startup.
2) Slow throttle, the car seems to be in limp mode and it accelerates really slow.
3) It allows me to go into second gear but won't shift above that.
4) Shift from 1st to 2nd gear is really rough.
Any input would be greatly appreciated.
10-10-2011, 01:55 PM
#20
Tsx6363: I am not one to necessarily provide much insight in these matters, though i've most certainly fixed lots of things on my own Acura. However, what I am good at is putting clues together to solve things (sometimes, anyway). Based on the battery dying and the codes you listed each having two possible electrical causes, if it were me, I'd check the following items.
1) Make sure battery cables are not loose and that the negative cable is grounded correctly.
2) Check all your fuses. Obviously, it's probably best to start with the ones pertinent to your issue (ECU, throttle, battery), but heck, I'd check each one.
3) With wire brush or a toothbrush, a 10 mm socket, and a flashlight, I'd go looking for all the ground connections. There are a few that are hard to get to, but there are at least three that I can think of that are pretty easily reached. Make sure they're clean and tight.
4) Recheck your recent work: is the new APP sensor securely plugged in? Is the area around the sensor clean and free of gunk, etc.? Is the throttle cable in the right position?
5) After you check all of those things, I'd remove the negative cable from the battery terminal for 10 minutes. The Helms manual lists a way to reset the electronics by crossing the battery cables (off the battery, of course) for about 15 minutes. Look that up before you do it, don't take my word for it.
1) Make sure battery cables are not loose and that the negative cable is grounded correctly.
2) Check all your fuses. Obviously, it's probably best to start with the ones pertinent to your issue (ECU, throttle, battery), but heck, I'd check each one.
3) With wire brush or a toothbrush, a 10 mm socket, and a flashlight, I'd go looking for all the ground connections. There are a few that are hard to get to, but there are at least three that I can think of that are pretty easily reached. Make sure they're clean and tight.
4) Recheck your recent work: is the new APP sensor securely plugged in? Is the area around the sensor clean and free of gunk, etc.? Is the throttle cable in the right position?
5) After you check all of those things, I'd remove the negative cable from the battery terminal for 10 minutes. The Helms manual lists a way to reset the electronics by crossing the battery cables (off the battery, of course) for about 15 minutes. Look that up before you do it, don't take my word for it.
10-10-2011, 01:57 PM
#21
As simple as #1 sounds, that actually caused a problem for me. I'd done something with the car (can't remember now), and I guess the negative battery cable wasn't tightened enough to the car. I hot a bump, and the electronics flickered for just a second. It took me about 10 min. to figure out the cable was loose. I tightened it, and all was well.
10-11-2011, 09:06 PM
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Tsx6363: I am not one to necessarily provide much insight in these matters, though i've most certainly fixed lots of things on my own Acura. However, what I am good at is putting clues together to solve things (sometimes, anyway). Based on the battery dying and the codes you listed each having two possible electrical causes, if it were me, I'd check the following items.
1) Make sure battery cables are not loose and that the negative cable is grounded correctly.
2) Check all your fuses. Obviously, it's probably best to start with the ones pertinent to your issue (ECU, throttle, battery), but heck, I'd check each one.
3) With wire brush or a toothbrush, a 10 mm socket, and a flashlight, I'd go looking for all the ground connections. There are a few that are hard to get to, but there are at least three that I can think of that are pretty easily reached. Make sure they're clean and tight.
4) Recheck your recent work: is the new APP sensor securely plugged in? Is the area around the sensor clean and free of gunk, etc.? Is the throttle cable in the right position?
5) After you check all of those things, I'd remove the negative cable from the battery terminal for 10 minutes. The Helms manual lists a way to reset the electronics by crossing the battery cables (off the battery, of course) for about 15 minutes. Look that up before you do it, don't take my word for it.
1) Make sure battery cables are not loose and that the negative cable is grounded correctly.
2) Check all your fuses. Obviously, it's probably best to start with the ones pertinent to your issue (ECU, throttle, battery), but heck, I'd check each one.
3) With wire brush or a toothbrush, a 10 mm socket, and a flashlight, I'd go looking for all the ground connections. There are a few that are hard to get to, but there are at least three that I can think of that are pretty easily reached. Make sure they're clean and tight.
4) Recheck your recent work: is the new APP sensor securely plugged in? Is the area around the sensor clean and free of gunk, etc.? Is the throttle cable in the right position?
5) After you check all of those things, I'd remove the negative cable from the battery terminal for 10 minutes. The Helms manual lists a way to reset the electronics by crossing the battery cables (off the battery, of course) for about 15 minutes. Look that up before you do it, don't take my word for it.
1) did it
2) did it
3) I'll do it tomorrow.
4) Something i've noticed about the plug.. it has a hard time snapping in. Does anyone have an issue with that? i'm wondering if it's the harness. I also cleaned it out with electrical contact cleaner.
Throttle cable i assume is fine.. I tightened it all the way and the problem hasn't come back... yet. Knock on wood** Although the idle is still rough on the way down... rpms kind of bob for a couple seconds before dropping down to 700-1k.
5) I don't quite understand what you mean by crossing the battery cables.. can anyone elaborate? or scan the manual?
In addition i've also cleaned out the throttle body.. Do you think cleaning out the TPS sensor will help?
10-11-2011, 11:10 PM
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i don't know if this is related but since my shifter light went out, i took it apart, but it seems the power supply is dead? its connected to the same harness as the shifter.. could that be a problem? not sure if both are dead, i'll test tomorrow.
yay for electrical problems
yay for electrical problems
11-03-2011, 04:05 AM
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update: After replacing the APP sensor, the problem was still there. My next guess was the TPS sensor, but before I replaced it i figured I would have it diagnosed to make sure i'm replacing the right part.
$200 in diagnostic fees leads to yes, it is the TPS sensor. So I just ordered a new throttle body and i'll update you on how this goes. I also had the tech test the new/old APP sensor, so if everything goes well after i replace the throttle body I'll have an APP sensor FS! Lemme know if anyones interested!
FYI the TPS is built INTO the throttle body, theres no way to remove it. It's encased in the metal housing and only the plugs stick out. That black part with the torx screws house the gears that turn the throttle plate.
Hopefully this will help someone out in the future thats in my predicament!
$200 in diagnostic fees leads to yes, it is the TPS sensor. So I just ordered a new throttle body and i'll update you on how this goes. I also had the tech test the new/old APP sensor, so if everything goes well after i replace the throttle body I'll have an APP sensor FS! Lemme know if anyones interested!
FYI the TPS is built INTO the throttle body, theres no way to remove it. It's encased in the metal housing and only the plugs stick out. That black part with the torx screws house the gears that turn the throttle plate.
Hopefully this will help someone out in the future thats in my predicament!
11-03-2011, 02:47 PM
#28
11-08-2011, 05:49 PM
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replaced the tps sensor... fine for a week. Problems back. Not sure what to do anymore...
Do you think i can bring it back to the shop that diagnosed it to complain? I mean i paid $200 and they said replacing the throttle body would fix the problem...
Do you think i can bring it back to the shop that diagnosed it to complain? I mean i paid $200 and they said replacing the throttle body would fix the problem...
06-30-2012, 07:50 PM
#34
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had to register to say "thanks!"
new app sensor fixed my 04 tsx with 107k.
i was getting the VSA light every few days. "cruising" was stuttering. lurching starts, etc. BUT, when I was on the highway with cruise control it was smooooth. So, got a P2138 code. read these forums. ordered the part.
20 minute job. smooth as butter now.
thanks again!!
new app sensor fixed my 04 tsx with 107k.
i was getting the VSA light every few days. "cruising" was stuttering. lurching starts, etc. BUT, when I was on the highway with cruise control it was smooooth. So, got a P2138 code. read these forums. ordered the part.
20 minute job. smooth as butter now.
thanks again!!
07-23-2013, 04:40 PM
#35
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Just wanted to say I had this identical issue and replaced my app sensor today myself and my 04 tsx is like brand new again! 400k miles and an easy fix I was willing to do with such an old car.
Here is what happened. Over the last few months on freeway driving the car would loose power in small bursts for half a second. This would come and go, some days nothing, some days it was bad enough to trip the vsa and throw check engine light. But I was never able to get the code because it would clear itself after a few hours. The stutter would only happen on really hot days over 95 degrees F, but when it was cool outside it was fine.
This happened for a few months. Last night I had the problem, immediately plugged in my scanner and got code p2138. Searched and sure enough found this thread as well as many TL owners with the same issue.
Local dealer had the part in stock, I paid high for it cause I'm in a rush with no backup vehicle. $200 at Acura for app sensor 37971-rbb-003. Took me 20 min and had the part changed myself. Used my Acura service manual of course.
Car runs great now. The problem was worse than I thought now that I see the proper acceleration. With 400k miles I guess its acceptable to replace this. Used 10mm ratchet with extension and 12mm open wrench. That's it. Thanks guys for the awesome info.
Here is what happened. Over the last few months on freeway driving the car would loose power in small bursts for half a second. This would come and go, some days nothing, some days it was bad enough to trip the vsa and throw check engine light. But I was never able to get the code because it would clear itself after a few hours. The stutter would only happen on really hot days over 95 degrees F, but when it was cool outside it was fine.
This happened for a few months. Last night I had the problem, immediately plugged in my scanner and got code p2138. Searched and sure enough found this thread as well as many TL owners with the same issue.
Local dealer had the part in stock, I paid high for it cause I'm in a rush with no backup vehicle. $200 at Acura for app sensor 37971-rbb-003. Took me 20 min and had the part changed myself. Used my Acura service manual of course.
Car runs great now. The problem was worse than I thought now that I see the proper acceleration. With 400k miles I guess its acceptable to replace this. Used 10mm ratchet with extension and 12mm open wrench. That's it. Thanks guys for the awesome info.
Last edited by RogerPodacter; 07-23-2013 at 04:44 PM.
10-18-2013, 06:39 AM
#37
Instructor
Did my swap tonight.
Initial on throttle lag is gone. On/off throttle jerk while in gear is still there though. My issue was mainly pulling out and shifting. Fixed
Notes: make sure to check throttle cable slack first. Adjust and test drive. That may solve some people's issues.
When installing make sure cable is reinstalled without slack as well
Initial on throttle lag is gone. On/off throttle jerk while in gear is still there though. My issue was mainly pulling out and shifting. Fixed
Notes: make sure to check throttle cable slack first. Adjust and test drive. That may solve some people's issues.
When installing make sure cable is reinstalled without slack as well
The following users liked this post:
witzy22 (05-23-2014)
05-23-2014, 05:09 PM
#38
Awesome Acura resource, thanks for all the info!!
I know no thing about fixing cars. This was my first DIY attempt. To all who posted how to replace the app sensor, I cannot thank you enough! Took me a few times to figure out how to tighten the cable correctly but successfully completed the DIY in about an hour.
I was having the same acceleration issues as others reported in my 2004 TL (125K). Recently got the same P2138 - Accelerator Pedal Position Throttle Position Sensor D/E Incorrect Voltage Correlation code the other day. Engine light and VSA light came on while driving and the car only ran in 3rd gear. Once I restarted the car that issue corrected itself.
Used the code to search the Internet and found this thread. Found the part number for the app sensor and ordered it off eBay of all places. $145 new incld shipping, no auto parts stores in the area had the part.
Once again thank you to all!
I know no thing about fixing cars. This was my first DIY attempt. To all who posted how to replace the app sensor, I cannot thank you enough! Took me a few times to figure out how to tighten the cable correctly but successfully completed the DIY in about an hour.
I was having the same acceleration issues as others reported in my 2004 TL (125K). Recently got the same P2138 - Accelerator Pedal Position Throttle Position Sensor D/E Incorrect Voltage Correlation code the other day. Engine light and VSA light came on while driving and the car only ran in 3rd gear. Once I restarted the car that issue corrected itself.
Used the code to search the Internet and found this thread. Found the part number for the app sensor and ordered it off eBay of all places. $145 new incld shipping, no auto parts stores in the area had the part.
Once again thank you to all!
07-02-2014, 10:48 AM
#39
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Would also like to relay my thanks. I've been experiencing accelerating issues for well over a year on my 06 6MT, with no codes showing up, just really jerky switching gears and no more smooth acceleration. I could barely climb to 2000RPM in 1st gear without the car jerking really bad, which I had to pay close attention to how I accelerate and how I clutch in order to minimize it. It got so bad to the point where I would kick it into first gear and throw it into 2nd as soon as the car started moving.
After a year of these symptoms, I decided it was the APP sensor going bad. I ordered the parts and it came in the same day that my dash board became a light show, VSA/Check emissions, sporadic pull back on engine when accelerating and with the new part installed, which literally took 5 minutes, the car is driving like it when I bought new.
I also put my car on a scanner again, and P2138 came up. So yep, it was the sensor.
After a year of these symptoms, I decided it was the APP sensor going bad. I ordered the parts and it came in the same day that my dash board became a light show, VSA/Check emissions, sporadic pull back on engine when accelerating and with the new part installed, which literally took 5 minutes, the car is driving like it when I bought new.
I also put my car on a scanner again, and P2138 came up. So yep, it was the sensor.
08-02-2015, 07:54 PM
#40
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What were the symptoms of your TSX if you don't mind me asking? I have a TSX and I am experiencing no acceleration. But the engine turns on. I do get those lights the VSA and check engine along with ! but when I turn off the car it stops for a while and then it happens again. But now there is no acceleration.