NE14RoxCJ

I've had this nagging problem with my 04 Auto for a while now. While driving at light throttle, I get a slight loss of power for a second or two at a time. It feels like the AC compressor cycling on and off, but it does it when the HVAC system is "off". Also, the AC doesn't cause this much drag. This happens at any speed while engine RPM is between 1800 and 4000.

AND, as soon as I ease into the gas again, it is very sluggish and doesn't want to pick up (unless it downshifts). VTec is still plenty powerful. Pulling through that RPM band (especially 2400-3800) is, well, ratchety. Not smooth. It seems like there is some type of "event" at 2800 and again at 3400RPM. It feels like it is "overcoming" whatever is holding it back. By 3800 RPM it is pulling strong and if I get into V-Tec, it is all balls.

Now, @ 95k miles, I replaced the EGR valve on the advice of a couple of Honda techs (who don't even know each other). When I described the problem, they both said "EGR". So I put an $85 valve on it and it was fixed. Then, around 103k miles it started all over again. I decided to wait and see what happened after I did the whole 105k service. During that service, I removed the EGR valve and sprayed some carb cleaner in the ports. It seemed to help for a very short time. Now it is getting really bad again. Sometimes it feels like the car is going to quit when going down the interstate. OK, maybe not that extreme, but I have to push the gas down an extra half inch or more to keep my speed up.

Sorry for the long post. I wanted to explain the problem so someone might be able to help. At this point, I am planning to order another EGR valve and maybe an IAT sensor. I hate to waste another $100 if I could find the problem elsewhere. Thanks for any advice (other than "take it to the dealer").

NE14RoxCJ

I just went and drove around with my Snap-On MT2500 scanner hooked up (Generic OBD2 only). Car was acting up constantly at cruise (normal, lately). I couldn't see anything out of the ordinary, but the scanner only updates parameters every few seconds, so if there was a quick/intermittent problem, I might not see it. IAT was normal around 100F. So I'll probably not waste that money. I have no indication of what the EGR is doing, though. I wish I could see that. I see the post is getting lots of reads. Anyone got any ideas??

sunny201

I had something similar to this and it would only happen in 3rd (I cant remember if this was only 2nd or 3rd gears). I changed out my tranny fluid and it went away and hasnt came back for 8 months.

Idk how long youve owned the car, but try to figure out the last time that the tranny fluid was changed. I think its recommended every 60K miles? If its never been changed get a 3x3 tranny fluid flush done.

my

asbestos

I have been dealing with this as well. About the first 10% of accelerator travel provides for jerky starts from a stop, making smoothness in rain etc difficult. If I punch it to, say, 20%+ it's normal... As you said, ratchety is a great word to describe it.

From what I've read, it could be due to clogged fuel injectors. There are techniques for dissolving the crud. What type of fuel do you use? Previous owner of mine used regular often...

Check this post, a guy with similar symptoms, and he had his injectors cleaned with good results (see final post there):

https://acurazine.com/forums/2g-tl-1999-2003-98/low-rpm-hesitation-589369/

Calling the dealer soon. Will be watching this one.

GetAcura

Dont belive its a trans issue. That woudl almost certainly show up on your scanner. Im thinking more of a breathing problem. That mileage is not typical of a converter issue unless the car is driven VERY hard. Older ones will clog the converter at 140ish.

NE14RoxCJ

Just did it. I got the car @ 74k miles. I got a message telling me to change trans fluid around 82k or 85k, I think. I did the 1x drain and fill since the guy at the acura place said that is all they do unless there is a problem. I didn't have any problems then. Also, with my latest "big" service, I did another 1x drain and fill, the trans filter cartridge, and the 3rd and 4th pressure switches. No change. It does it in all gears, 2-5. Acceleration is crap in 2nd and 3rd, and the surging is more noticable in 4th and 5th. It's not a slipping problem. More like a "bogging" problem. But it's like it is on a switch being turned off and on randomly. I replaced the plugs a while back (before the 105k service). I think I did that when I was trying to figure it out the first time. I ended up changing the EGR valve and it seemed fixed. But why would a brand new EGR valve only last 10k miles? That is why I don't feel like dropping more cash on another valve if that isn't the problem. Thanks a lot for the reply, Sunny.

NE14RoxCJ

Breathing?? I put a K&N filter in it pretty soon after I got it. I cleaned and re-oiled the filter with the recent 105k service (actually it was 108k when I got the maint. minder).

My scanner doesn't show much. I don't have the proper modules for Acura, but it will read generic OBD2 codes and data. I didn't see anything about the trans in the menus. I think it is engine only.

When you say converter? Torque converter (transmission) or catalytic converter (exhaust)? Could I have a stopped up cat?? I try to blow it out pretty often. I even get that sulpher smell sometimes after driving the p*ss out of it. I'm not saying I flogg my car regularly, but I get into the upper RPM band occasionally. So what is "driven VERY hard"? This is my daily driver. It sees 75-85 MPH for the majority (~70%) of my 50 mile round trip. My message center says the average over 17,000 miles is 42mph and 22mpg. Thanks again for the replies. Maybe we'll get this figured soon. I'll probably order an EGR valve soon, since this is te only thing that has made a difference.

TL|GTX

Shit the same thing happend, when i thought i hydroclocked the engine. But it never happend since.

scv76_

I don't know if this is relevant to our TL engines, but I had a similar problem with my V6 accord back a few years ago.
After replacing the egr valve, engine started acting odd and finally threw a check engine light.
Turns out under the egr valve there was a clogged small diameter port that runs through the manifold into another chamber.
It was filled with carbon and the tech had to use a small drill and carefully clean the crap out of the hole being careful not to let the carbon go where it shouldn't

NE14RoxCJ

Yep, in fact the kit I bought was an EGR pipe kit that came with a small section of ~3/8" pipe. The Honda guys I talked to knew all too well about the problem. I guess it was a big issue with the 3.0 V6 Accords. BTW, the Honda kit is less expensive than the acura valve. The kit comes with the valve, gasket, piece of tubing, and a TB basket (which doesn't fit our intake). Seems like the 2nd gen TL's had a problem there too. Like every 75k miles they recommended the intake be removed and cleaned.

Well, I DID clean the hell out of my intake when I did the valve adjustment. It was all SOOO funky, I thought for sure that would fix the problem. And I swear I didn't feel it for a week after the "big" 105k service. But, now it is back and as noticable as it was just before I replaced the EGR valve the first time. I got that EGR stuck in my head, but it's only 15k miles old. Could the funk from the intake have trashed the new valve in that short of time?? Or at all? I can't imagine it.

NE14RoxCJ

AGGHHH!! It's getting worse every day. I just wish it would throw a code and be done with it. A guy at work mentioned the TPS. Well, on the TL, it would be the APP (accelerator pedal position) sensor. It kind of makes sense. When I set the cruise control (ie. not using the pedal), I don't even notice the surge. Maybe the ECM and Throttle Control Module just react to the change faster than I do. Maybe the Throttle Control Module doesn't have any problems, and it's that APP sensor that has a dead spot.

Thing is, I've read about the failures of the APP sensor on here, and they seem to just "go bad" and cause the trio of lights and set a code. I've seen this on old Fords and Chevy's, but I had hoped the Ac was smarter than that and would acknowledge a problem and set a code. I just can't believe my car can run like shit and not know it.

Anyway, APP sensor is more $$ than the IAT and EGR combined. @ $120+, I may just drive it and see if I cn get it to give up a DTC. Hell, I could buy all 3 parts and still come out smelling like a rose compared to taking it to the stealership.

Anyone have problems with their APP sensor??

01tl4tl

we are calling it TPS throttle position sensor for an international standard of discussion
Some gen2 have had that problem recently and required new TB iirc

Also check if you have vac assisted motor mounts (the front and rear ones)
if one goes bad and leaks its oil filling, it also developes a mystery vac leak

01tl4tl

whoever said to replace the egr valve was nuts-
we have to CLEAN to egr ports yes,,, but the valve is usully ok--it opens or it doesnt--some wd40 wont hurt, to be sure the egr spring is working

NE14RoxCJ

Ahh, vac leak was mentioned yesterday also. I totally forgot about the motor mounts. Anyone know off hand if ours are Vac assisted mounts? I know that the motor mount on the right side (the one I removed to get at the water pump and timing belt) was full of oil. I know because it all spilled out when I sat it on the floor. I had one shipped overnight along with some other parts I found that needed replacing.

I'll be checking into this right now.....

NE14RoxCJ

Sorry to answer my own Q: Yes, the front and rear engine mounts are vaccum assisted by electronic control (switching off and on like I described before.) Hmmm... I'll investigate and report back shortly.

01tl4tl

iirc gen3 vac mounts are to soften the engine vibrations at idle, (gen2 stiffens on throttle application)
but a vac leak is a vac leak, and fluid from one sitting on the garage floor is a bad sign~

Have you removed the intake manifold and cleaned the EGR ports (6) not just spray in at the egr valve?
and cleaning the intake runners and manifold throat with manifold off the car-
plus the TB butterfly plate needs to be spray cleaned with carb cleaner--more often with a K&N

On the K&N reoil- there is a specific Oz. amount of oil to be used on each size filter- says how much in the detailed instructions in the box
If you use too much oil it will get sucked off the filter and into the manifold, onto the plugs...thru the cat...not a good thing
Be precise and if in doubt- redo the cleaning and reoil

Plugs- NGK Iridium?
Take a few out and do a reading- plugs tell all~

Seafoam the manifold with engine running last when?

Use Redline fuel system cleaner- 1 bottle to 1/2 tank of gas will clean the injectors quick!

scv76_

01tl4tl beat me to it...I was just going to suggest a Seafoam procedure
I think you are on the right track concerning a possible vacuum problem, maybe check for a leak at the erg gasket you just had worked on?
Always learning..I had no idea our 3g motor mounts were vacuum assisted

miah2178

I have the 6MT and I experience the same surging problems at the same RPM range. It's an 04 TL with 145K+ miles. If I slow down then accel in gear quickly I get a "whip" from the motor. I suspect either rear or front motor mount. I was trying to look at them yesterday in the rain and noticed they are vastly different than my old '94 EG civic. I'm very curious if a vacuum leak on a broken motor mount could be causing the surging / whipping of the engine.

How would we go about checking if these parts are bad and would these be the replacement parts if they were bad?
RUBBER ASSY., FR. ENGINE MOUNTING (MT) 013 $148.13
RUBBER ASSY., rr. ENGINE MOUNTING (MT) 008 $112.86

What does this part do?
DAMPER ASSY., RR. ENGINE ROCK 012 $122.75

NE14RoxCJ

Thanks so much for your replies. The motor mount that I replaced was the right side mount. It is not vac assisted. The front and rear mounts are the only ones that are. I used my hand vac pump and checked the switch (manifold to switch). No leaks. I checked from the switch to the motor mounts, and it leaked very slowly. I don't think it would be enough to cause the surge, but I capped the manifold port and I'll go drive it around later.

I pulled the intake and cleaned every little passage when I did the 105k service. The EGR dumps into a small chamber at one end of the intake. It was really nasty. It comes up from the valve thru front head, thru a passage in the lower intake (?) and into the upper intake where it passes thru a small sheet metal "Y" mounted in the EGR chamber. Ports in that chamber carry the spent gases into the main runners of the intake. Everything is sparkling clean now. The only one I didn't clean real well was the passage from the EGR valve thru the front head and front "injector mount/runner." I wasn't sure where it went as it passed thru the head. I also cleaned the TB and replaced that gasket. The gasket on the EGR valve is new and tight.

The K&N filter: I installed it around 85k miles with the factory oil charge. The problem started soon after that, but I never thought that could cause it. Maybe I'll pick up a new paper filter.

Plugs: NGK Iridium replaced around 92-95k in searching for the problem the first time. I pulled the plugs when I did the 105k service and valve adjustment. I checked the gap (carefully) on a couple of them. All of the plugs looked good with just a slight tan color.

A friend who works at Nissan gave me their upper engine cleaning kit. Dumped a can in the tank with ~1/4 tank left. and sprayed the aerosol can into the crankcase vent line in front of the TB with the engine running. I know it's not Seafoam, but should be similar.

I've got the vac port for the motor mounts capped off for now and I'll drive it and see what happens. I'll report back after while...

Thanks again for the ideas. Maybe I'll be looking for a vac leak this weekend. Oh, what about the canister purge. Doesn't that take place at cruise speeds? Maybe another possible vac leak...

NE14RoxCJ

I think that if I find bad motor mounts, I'll be looking into the Innovative mount kit. For just a little more (or about the same price), you can upgrade to stronger mounts. They are NOT vac assisted. And they don't use weak rubber.

01tl4tl

watch those solid poly motor mounts- they take the smooth right out of a TL

beyond spraying cleaner into the pcv pipe opening in the snout- which does help but can be done better:
remove the rubber snout from airbox and spray the TB plate on both sides to remove crud sent from PCV!
gen3 turn key ON to cycle the TB plate in a self test- lets you spray clean the back side of it

see the gen2 diy on egr cleaning- inside the intake manifold are 6 ports for the egr- they get plugged with the carbon and cause poor engine running
Other than at full throttle and idle- the EGR is allowing exhaust gas to go into the manifold, all that time sending crud to the tiny 8mm passageways

Yes you do have to run carb cleaner or solvent thru each one after digging at it with a coat hanger or similar tool

Cant get much cleaning done simply by spraying into the EGR- some yes, but not the method needed by the TL
This is the only car Ive seen that requires frequent egr port cleanings- every 75k miles on gen2 is avaerage and they plug

01tl4tl

an egr valve failure that left it open would send exhaust gas to the intake at idle- make it run realllly bad- or at full throttle it would feel slugghish

if stuck closed- no exhaust gas to intake- the engine is happier than normal~

NE14RoxCJ

I just glanced thru the "DIY Thermoblock install/EGR cleaning" post on 2nd gen. I didn't see th 8mm ports you were referring to. Also, the 3rd gen manifold is a bit different. We have gone back to the "variable geometry intake runner blah, blah" system. So I have a top cover on the intake (it has "3.2 VTEC" embossed in it). Removing that, reveals the intake mounting bolts, butterfly valves that change the intake geometry, and the EGR chamber at the TB end. Do you know if I have these small EGR ports that you were referring to? Although I see what you mean about a failed EGR valve. Stuck closed would be best, but stuck open would dilute the mixture even at idle. The car idles very smooth, though.

I got some pics of the intake and the cleaning. I'll try to post a few when I get home from work or tomorrow.

I mentioned that I capped the vaccum port to the motor mount solenoid. I took a short drive (25-30 miles) and I think we may be onto something. I won't say anything yet, but I'll drive it to work this afternoon and see how it feels on the way home tonight. Keeping my fingers crossed...

01tl4tl, I hear ya on the motor mounts, but is the harshness similar to installing a heavier RSB? I don't wanna rattle my teeth or feel every piston fire. And for me, the factory mounts would be cheaper since I just replaced the right side mount. But are the softest of those Innovative mounts (60A?) too much for a daily driver?

miah2178

I noticed WAT (wide open throttle) and idle are both smooth. Once I theorized that humidity had something to do with the severity but it hasn't been dry here in WV for several weeks.

I have the HELM's manual for the '04 TL so I'll take a look and see what's all involved in cleaning the EGR ports.

01tl4tl

doh! - I did not know of the differances- in gen2 diy the egr ports are circled or pointed to, one per cylinder

That bad front mount has fooled other ziners~

NE14RoxCJ

miah2178, try this: find the vaccum switch/solenoid mounted on the back of the intake (remove the plastic intake cover). There is a short, 3" curved vac hose from the switch to a port on the intake. I removed the hose from the intake and put a cap on the port. I've driven about 80 miles since then, but I won't open my mouth yet. I will say that I didn't notice the surging last night on my drive home. Not claiming it's fixed, because I need to take a longer drive to convince myself. It'd be interesting to see if this helps with your poblem.

If this fixes my problem, I'll owe 01tl4tl a load of beer.

miah2178

Sweet, I'll try this tonight. I ordered a few parts from Excelerate Performance in hopes to do a thorough cleaning of the EGR ports along with taking PIC's so maybe this could help others later on.

On the other note, I still have to find the bad motor mount/torque rod that's bad. I think with the surging + loose engine it makes for an uncomfortable driving experience. It's been dry the past 2 days and it hasn't surged nearly as bad. It does it from cold start in 1st to 30 miles later in 6th.

miah2178

Removing the vac hose just makes the engine vibrate slightly through the steering wheel at idle. It didn't fix my engine surging. I hope to clean my EGR ports soon though and replace the torque damper.

NE14RoxCJ

Yeah, miah2178, my optimistic feeling was short lived, also. It started running like a drunk turtle again Saturday night. At the time, I was very low on gas and hoped I had found another clue. I filled it up with Valero Premium and its still acting up. I'm back down to half and it is just getting worse.

I'm still leaning toward a TPS (or APP sensor). When I got home and parked in the garage. I held the pedal down and tried to hold some various engine speeds (1800, 2000, 2500, 3000, etc.) 3K was easy to maintain, but I could NOT keep the engine at 2500 RPM. 2K was tough also. When I got to 2500, after a few seconds, it would drop ~100 RPM, then another 100-200 RPM. It stays there until I press the pedal further, then it speeds up over the original 2500. I really need a scanner that will read APP sensor voltage or %. Maybe I can catch it with my Fluke meter?

I'm not done searching yet...

NE14RoxCJ

OK, if anyone is still with me, I just pulled the intake hose off of the front of the TB. I removed the cover from the APP sensor (benind the stut brace on the pass. side). I turned the key on but didn't start the engine. While staring down the throat of the TB, I reached over and applied the throttle sowly. The butterfly in the TB was dancing all over the place!! Only until after 45-50% when it steadied up and was smooth all the way to WOT. I think I found a clue. Now, the ? is what to change? The cruise control seems to be smooth as glass, so I'm thinking the TB is OK. I might think the Drive-by-wire driver unit, but it's not hanging out in the engine bay. Any thoughts??

miah2178

That's a good idea. I'll try that. My cruise control is also smooth. I found it interesting they designed the APP sensor and cable length so that it "could" be retro-fitted back to the TB if they desired. I guess the drive by wire works better with the TCS.

I ordered a torque damper. I'm still planning on cleaning the EGR ports next week when I get the new gasket for the IM.

NE14RoxCJ

Please, miah2178, and anyone else willing to help. Try this procedure. I really want to see if someone with a "fault-free" car has a throttle blade that bounces. miah2178, your's may be doing the same exact thing as mine. I might have to go find a TL to test-drive and see if it does it. I suspect that a "proper" movement would be smooth and follow the APP sensor (like it does over 50%). 01tl4tl, have you seen this type of action from the TB? Or could you check yours and see what it does?? You do have a 3G TL don't you?

miah2178

Hey NE14RoxCJ. I did exactly what you suggested. My TB "bounced" as I moved the throttle cable in the first 30% of the movement and then it was smooth. I even noticed the butterfly valve to be bouncing when I held the throttle cable completely still. Now the question is, if it failed, which side failed, the APP or the TB side. I have the manual so I'll see what the diag is for each. I have an OHM meter but beyond that no specialized diag tools.

miah2178

The SENSOR ASSY., ACCELERATOR PEDAL is part 37971-RBB-003 and I found it for $119.
The THROTTLE BODY, ELECTRONIC CONTROL is part 16400-RCA-A01 and it's $272.59.

I'd rather it be the APP.

NE14RoxCJ

Exactly like mine. I could not get it to stay steady to save my life. I mentioned this in another post "05TL drives slow" or someting. IHateCars said he would check his also since he has no problems. I'd like to see if a good running car acts the same way. He and I agree that the programmers could have written something in the code to do just what its doing. I doubt it, but you nevr know.

Anyway, if I go throw parts at mine, I'll start with the APP sensor. I say that because I can't feel any surging with the cruise control on. I would think that if the TB was bad, it would have problems with the cruise also. I thought the VSA might have something to do with it, but I turned it off on the way to work yesterday and it still did the same thing. Also, the APP sensor is half the price of the TB. If that fixes it, I'll stop there. If not, I'll bite the bullet and try a TB. Either way, I'll come out spending less than taking it to a dealer and leaving it for god-knows how long. Let me check that other post and see if anyone else said anything. I'll let you know if I decide to order an APP sensor.

miah2178

Looking at the manual, there are 2 other components to the Electronic Throttle system. The throttle actuator control module and the throttle actuator control module relay. Both are inside the car in the center console ride side near the passengers feet.

The diag for all these components are either check for continuity between wires, check for voltage, or "replace with a known good" part. I suspect continuity and voltage will be fine as we have an "intermittent" problem at certain voltage ranges.

What do you think?

miah2178

That makes sense with the Cruise being smooth. Are you for sure the cruise by-passes the APP altogether? I remember when using cruise the pedal is usually depressed to match the cruise throttle amount.

As much as I hate buying a part that isn't needed, the APP does seem to be a "common" fail point. Does your TB squeal when running that test? It's a really high pitch.

NE14RoxCJ

Yep, really high pitch squeal when it is moving at all. when it is steady, it is quiet. I'm all into R/C cars also, and I hear servos making that noise when they are goinng bad. you know, they always make a little noise, but when they are still they are quiet.

I'm not sure what each componenet does, but it seems that the Cruise control works fine. that makes me think that the driver module works fine. Unless the input to the driver module is messed up some how. But I feel like the APP's output would be f'ed up somehow before the driver module's input. I'm still waiting for someone to tell me theirs is smooth all the way through. Otherwise, i've almost convinced myself to order an APP sesnsor. I'll be the guinea pig if Monday rolls around.

miah2178

I went ahead and ordered the APP. I think you convinced me enough to feel that it's a safe bet. If it was the TB side, I would expect the cruise control to be equally faulty. I've noticed several threads + google search on APP sensor replacement results fixing our problem.

I also saw a TSB about the seat position memory module going bad and mine has so I ordered that as well. Can't wait till all the parts roll in. I'll have the car back to top notch by this weekend. Fingers crossed...

NE14RoxCJ

I just now pulled the trigger on one also. I guess we'll both find out soon. I ordered from acuraOEMparts along with some other stuff also. Just a couple of those special light bulbs. Let me know when you get your APPS replaced. Or I will chime in when I get mine.