Just checking in......not much of an update......but I think the Acura is still giving us a clue that I cannot understand.

Acura is better since Acura replaced all plenum set gaskets. But fluctuating idle still occurs.

Main Clue:

In Park, idle revs up and down, intermittently.
When this happens, I put the car in drive for about 10 seconds, then back into Park, and then miraculously the idle is perfect.
The other day it revved up and down when I was parked on an incline. I moved to a "flat" parking spot, and the idle was fine.
Strange clue....

 

Hi everyone. If I can just describe my own idle problems right here instead of starting a new thread. So recently I had my shop install a new (used) set of injectors, since my old ones sort of fell apart (the plastic tips were bad, to the point you couldn't even fit the O-rings onto them). After fitting new injectors the car wouldn't run at all (the theory is that there was air leaking through the injector ports, and fixing that leak starved the engine of air). I fixed that by modifying the B-series TB to J-series adapter setup. The car ran fine for a few weeks, but now I've got a new problem. In short, right after cold starting the motor, the car runs fine for a few minutes, but then all kinds of unpleasantness start occurring - hunting revs, the engine refusing to hold idle and stalling. When I hold the throttle open, the motor seems to be running rich (judging by the smell of the exhaust gases). Pumping the brake pedal helps a bit for whatever reason, and the problem completely goes away as soon as the motor fully warms up. I've replaced everything I could think of - IACV, FITV, coils, EVAP canister and purge solenoid, throttle body gasket, the spark plugs are new, throttle body is more or less clean and properly calibrated, the car isn't throwing any codes.

To be clear, I'm not asking anyone to guess what I might be dealing with here. But it'd be super cool if someone could help me rule a few things out, since I am a bit stupid and have a tendency to (inefficiently) throw money at these sorts of problems. Is it safe to assume that the intake manifold gaskets aren't to blame (the two between the lower runners and the heads, and the one between the lower runners and the upper intake manifold)? I couldn't find any related posts on the forum, so I take it nobody ever really replaces them, unless they were somehow physically damaged? And could the problem be related to the fuel pressure reg or the PCV valve? Thanks in advance. Almost forgot - my engine is a J32A2.

 

Latest Update:

I have not taken car to new mechanic yet......car has been driving OK so I have been saving money before putting it under the knife again.

Although something NEW:

Heavy amount of steam coming from coolant reservoir after turning car off. This has happened multiple times now. When this happens....and I put car in park.....the RPMs do their thing.....rev UP AND DOWN. This has been getting better.....the revving RPM has been more infrequent, but ALWAYS acts up when the "steam" situation happens.

Anyway....today I opened the radiator cap to check levels and noticed the radiator cap is shot. The spring is sitting in the radiator. It is in several parts. Basically looks like the photo I found online. Today I will replace the radiator cap. Wouldn't it be some sh*t if the problem all along, was a bad radiator cap. The one thing I know for sure is.......the revving RPMS had nothing to do with idle air valve or throttle body. It had to do with bad mechanic leaving vacuum leaks. Acura replaced all plenum (and throttle body) gaskets and the problem was almost 100% resolved. This problem is hand and hand with a coolant system issue.

 

FML
(can't wait to light this car on fire or crash it into a canyon).

Went to grab the radiator cap but car would not start. No power to anything. Replaced battery with brand new from Autozone. Still wont start.
I intermittently get full power, but as soon as I go to turn car over, all power (dash lights, blower motor, etc.) goes out. Then full power will not come back on for a few
minutes or until I keep messing with the key/ignition. Dashlights come on (sometimes), everything else comes on, but when I turn key nothing happens except all the dashlights go out.
Something electrical. So whatever. I give up.

 

Update:

Removed battery terminals....cleaned up battery posts and the clamps.....electrical tape on some frayed area......sandpaper.....cleaned......cursed......c leaned.....
Installed old battery.....car started right up!
Returned new battery for a refund.

Also installed new radiator cap.....

 

Well don't leave us hanging, did the new radiator cap change anything?

 

Ha! Well.....the coolant reservoir stopped steaming. But the RPM situation went from sporadic to frequent/most of the time. As of right now, the Acura is at my new mechanic. It is being diagnosed today. I will revert back with their findings. Thank you!!

 

I was working on a 4-cylinder '01 Accord a few months ago that had a similar issue - that ended up being part air in the coolant, part bad throttle position sensor. Different engines and all, but might help with your troubleshooting!

 

I am convinced the issue is due to something in the coolant system (air, pressure, leak, etc.).

 

Just got off phone with mechanic (3:15PM Eastern). Car has been there all day. They have no idea what the problem is. They said they will call me back.
Just lovely.

 

As of 5:15PM pacific, H-Tech Auto Las Vegas has no idea what is wrong with the car....no idea why the RPMs keep revving/fluctuating. They also wouldnt put the head mechanic on to tell me what they ruled out.
All they said was they need more time and they need to check everything (in an effort to keep my cost down). I'm about ready to give up. Just had the transmission rebuilt 15k miles ago.....engine runs perfect when it isnt pulling
this bullshit......but now wonder why I sold my American car before moving here.

 

Question: If I take the car to some other asshole and have them do a power flush/replace of the coolant, will that eliminate all air from the system (assuming that is the problem)?

 

I was thinking about this last night when I was folding laundry - you mentioned at some point that you replaced the IACV with a junkyard part or something, right? Maybe it was another part.
Either way, I was working on a weird idle issue on my '99 TL two summers ago and tried using some junkyard IACVs, after giving them super thorough cleanings. They would perform slightly better than what I had, but still not ideal. I finally bit the bullet and coughed up the cash to get a brand new part, and that ended up solving that part of the issue.

Probably not directly relevant to your scenario, but if you've still got some re-used junkyard parts that you swapped in, maybe consider buying new? I always have to remind myself that when I pull a part from the yard for my car, it's likely two decades old at this point and probably not in better condition than what I've got.

As far as coolant flush goes, it's all basically the same process no matter who does it. You could try it yourself if you wanted, just get one of those locking coolant funnels to help out. Save yourself some money in exchange for some time spent outside with the TL.

 

 

As as far as the IACV goes....I replaced with new and used.....I am on my 4th and it does nothing to change to problem.

I picked the car up last night from the mechanic and the revving RPMs seemed to be better, more intermittent. The RPMs did rev up and down in park when I was at a drive through, but I then turned the temperature setting inside the car to hot and put the car in drive then back in park and it stopped revving. Then at another drive through the temp gauge on the dash was very hot...the temp kept rising. I put the heat on full blast and the temp went back to normal. As all of this was happening, in park, the RPMs did not rev. Everything was normal.

Today I am going to get a thermostat and burp the system (I will buy the special funnel). I continue to think this is coolant system related. The dashboard temp gauge rising to almost overheating, then back down again, and the intermittent RPM rev makes me think it is all related. At this point, doing what I am going to do today cant hurt. Thanks!

 

From my rather casual understanding of our engines, it definitely does sound coolant related. Hopefully the new thermostat and burp does it!

 

The mechanic called me back....wanted to know if I wanted to schedule time next week for him to spend the entire day on the car.
I told him I am working to install a thermostat.
He then proceeds to tell me that the thermostat isnt a problem.....but instead.....I need a lower fan sensor because the fan is not coming on as it should.
I wish I would have known this last night. I think the sensor will fix the fluctuating temperature, but I do not think it will fix the RPM situation...

 

Someone told me on here that our RPM is heavily controlled by the coolant - so it may be part of it.

 

Update

Just checking in:

Car is running OK although the idle problem is still intermittent. I am not always getting revving RPMs when in Park. I am ignoring it for now so I can save money before getting it diagnosed (again) and repaired.
Right now, it is intermittent, and often when the RPMs rev up and down in Park, I then put car in drive, then back in park, and then the RPMs will normalize. Sometimes
I have to do this two or three times, and sometimes turn the AC off and on (and mess with the dashboard temp gauge), but usually it works and the RPMs in park stop revving.

This tells me the problem is NOT vacuum. Moving the gear from Park to Drive then back to Park again, would not make a vacuum problem get better. This tells me the problem isn't intake manifold gasket (besides I have no other symptoms) because that problem, again, would not magically get better when I move car from Park to Drive then back to Park again.

The question to me is: Why can I make the up-and-down RPMS in Park go back to normal by going from Park to Drive? Why does this fix the problem? What is occurring when going from Park to Drive then back to Park to make the RPMs normalize?

 

so have you burped your car's radiator yet?

 

I have not. Been frustrated and just felt like not paying it much attention. I have before using the car, opened the radiator and squeezed the hoses and then added a little coolant to fill radiator (it didnt take much).
it just makes no sense that one minute I can go into Park at a drive-thru window, and have ZERO problems.
Then I can drive another 15 minutes and put car in Park to go into a store, and the RPMs will go up and down.
Then I can get it corrected by messing around and throwing it in and out of Drive.

Admittedly I should have burped system (although Acura told me they tried this before) and admittedly I have been a bit pissy with this car right now. I will get back on the horse soon.

 

Hey, any updates on this Domenic?

 

Any update Dominic? I have the same issue on a 2000 acura tl v6 3.2L with the idle surge (revving up and down). The codes that showed up for me were p0135 and p0505 . The auto zone solution i got printed out said to replace oxygen sensor bank 1 sensor 1 *before the catalytic converter, did that and it did not fix the idle surge. I checked the idle air control valve, it look clean but, i guess it needs replacing...i don't know. Does anyone know the solution to this?
The person i bought the car from said it could just need the computer reprogrammed. A non dealership acura and Honda specialist mechanic said you don't do that, it's probably needing coolant or could be a solenoid.

Anyone have any do it yourself solutions before i take it to that acura and Honda mechanic? Thank you.

 

^
Make sure the vacuum tubes at #11, on the link below, are securely connected. The upper one goes down for the engine mounts as shown on the diagram. The lower one runs to the rear of the intake manifold.
Engine Mount for 2000 Acura TL SEDAN | Acura OEM Parts

Sometimes cleaning the throttle body can help if it is dirty or full of sludge. Or you can either have the mechanic clean the existing IAC valve or replace it.
Make sure to get a quality aftermarket one, like the one below from RockAuto. They are about $66 shipped:
More Information for STANDARD MOTOR PRODUCTS AC229 (rockauto.com)
The OEM ones are about $250 shipped.
Good Luck!

 

Thank you @zeta for the information!
Going off by the picture i couldn't tell which was the part but, i didn't find any disconnected or damaged lines. I will be replacing the idle control valve in about 2 days, a youtube video showed then replacing it on a 1999 acura tl v6 3.2L and it fixed the problem! I'm on a budget so I'm looking for help on youtube. I know it didn't help Dominic unfortunately. As far as cleaning sludge from i think you said manifold, I didn't think I had to but I'll send pictures. I'm not too experienced with cars, I just got this 2000 acura tl v6 3.2L automatic car a week ago and seemed like a opportunity, paying 1500 for it, only having 168k miles and looking like it only needed motor mounts and the idle surge fixed. I wouldn't be able to go through the money spending process like Dominic, great guy explaining to us the troubleshooting process in his case.
*To help him and others with this problem in their 2000 acura tl v6 3.2L automatic, does this car have a (cold fast idle), like their is on 97-99 acura integras? I saw a popular youtube video where they find it under the idle control valve, take it out, adjust it and it solves the problem!
Anyone know?, thank you.

 

Update, and thanks zeta for the help. I fixed the up and down revving by replacing the idle air control valve, then doing a (idle relearn procedure). The video is at youtube channel (mods forever) 15 minute video with a throttle body as the thumbnail, enjoy! I think these relearning hacks are the hidden knowledge mechanics aren't helping us out with.. well secrets out! Enjoy everybody!

 

Hello everyone - I meant to post an update a while ago but it slipped my mind.
Though the revving idle in park is sporadic, yes, it still occurs. Despite every feasible fix and tried solution.
When the revving happens (in park), I turn the AC on and then off, and that generally stops the revving. I also can stop the revving by going into reverse then back into park, or going into drive then back into park. Sometimes the revving will fix itself if I ignore it for a minute or two max.
I cannot see the problem being a vacuum leak or IACV issue or air in coolant system (replaced radiator and fluid last year).
if you consider the "fixes" I previously mentioned, this seems like a ECU/computer issue. It doesn't happen enough for me to bother with fixing it. Just annoying.

That's the latest! Thanks everyone. Be happy and safe in 2022!

 

I'm having a same problem on my rsx for months now. Soon, my next attempt to fix is changing the spark plugs, re-learn the idle procedure, and lastly buy a kpro and give it a tune. My assumption is problem could come from ecu.

 

I have the free solution for post 67 and post 68.

 

I have already done that but it couldn't fix my issue.

 

Maybe the trick is, what worked for me twice, is doing the relearn procedure on a cold start * first start of the day. On top of that I would follow the directions of modsforever *youtube channel exactly, and always have someone to help you see when the radiator fans come on. You'll know it's working when your trying to get the rpm at exactly the instructed number and the car seems to help automatically.

 

New Reply

As you have read, this issue for me is sporadic. Which in itself is weird, because I think most folks that have this issue experience it "all the time/most of the time".

A few days ago the issue (revving idle in park/neutral) occurred and was severe. CEL and TCS light both illuminated. And, there was an issue driving the car, which isn't normally the case.

I checked coolant level, checked for vacuum leaks for the 975th time, cleaned the IACV. Lastly, I disconnected the battery for hours and once engine was cold, reconnected battery and did idle relearn (3 fan cycles). Next day, car operated without issue. It was as if the issue never occurred. Like....resetting the computer did the track. Now having said that, there were instances where when I put the car in Park, the idle would rev up and down. But it either quickly corrected itself, or in one instance, I turned on the AC and turned it off immediately, and the idle rev fixed itself, immediately (that to me is weird and tells me it is not vacuum or value related).

The other night, issue was like grim death. Now, it isn't occurring.

I am ready to purchase an ECM from Ebay and have it programmed at Acura. I know the general reasons for this issue are coolant levels, vacuum leak, bad IACV, possible gasket leaks drawing vacuum. But to me, this continues to smell like an ECU issue. Perhaps an electrical/ground issue, but who knows.

So, I am going to most likely grab the ECM and reply back with findings.

Thank you for dealing with me and reading all of my annoying posts. Honestly, your back-and-forth and experiences have been extremely helpful!

 

Quick response for now but, I think ericthecarguy.com would be able to permanently help you. He used to be an 8 year Acura technician/Mechanic and i think 20 year total experience as a tech/ Mechanic. I think he would work on 96-04 acura/ Honda, good luck man.

 

Update (Oct. 2022)

Let me refresh the situation - this all started following a local mechanic replacing a valve cover gasket. Once the mechanic put everything back together, the car started having the revving idle problem.
I have been dealing with this problem ever since....for approximately 2 years. It has always been intermittent. I dealt with it. I found ways to make it stop temporarily or I ignored it.

A few weeks ago the problem stopped being intermittent and became constant. It was affecting the way the car would drive and it was revving while driving; using alot of gas. It happened every time I used the car. Constant.

So...I purchased a new IAC (InterMotor) and attempted to replace. However, the screws holding the IAC to the throttle body were stripped and would not come off. I used screw extractors. I used a drill. Nothing. They were on there for life! Went to junk yard and purchased a throttle body. Took it home....cleaned the F out of it.....made it look brand new.

I installed the new IAC on the junkyard throttle body. I performed idle relearn. The problem is now GONE. The problem has not come back (over 1 week), even if I am in park or neutral. No matter how hot or cold the engine is. No matter how far I drive. The problem is 100% gone and the car actually runs GREAT - - - it is more calm and idles as if it was brand new.

There is something to add. Recall above when I told you the local mechanic performed a valve cover gasket replacement, and put EVERYTHING back together? Well when I purchased the vehicle in 2016, I noticed the cruise control cable which connects to the throttle body, was off. I never thought anything of it. Because I never needed cruise control. When the local mechanic put everything back (as did other mechanics since), he reconnected the cruise control cable. This time, for whatever reason, I decided to leave the cable off. So......was the fix the InterMotor IAC? Was it the throttle body? Was it the cruise control cable? Beats me and I am not going to try and find out. All I know is that FINALLY the situation is resolved! FIXED!

The next item "fix" I am going to handle is having both valve covers gaskets replaced. (Apparently the last time I had this job done, I used cheap ebay gaskets and they are leaking). Leak isnt affecting the amount of oil on dip stick. Honestly, I only want to do it because of the smell. And sometimes I get a bit of light white smoke from the oil leaking from the gasket onto a hot engine or exhaust part. I know that when someone does this job for me, I need to buy a very good quality (Honda, but pricey) valve cover gaskets with tube and plug seals, both plenum gaskets, new plugs and I may get new coils (I want Denso coils....the ones are there now are aftermarket).

Thank you for reading!!!

 

************************
New update: Oct. 23
As of this weekend, the problem is back again. What in the actual fuck? Fucking car ran perfect for weeks after I changed the throttle body with a new IAC. Absolutely perfect. It even sounded better and overall just seemed to run better. So why now? If the problem was vacuum leak, intake restriction, loose wire, or God knows what else, it would not have disssapeared for over 2 weeks.
At this point the only thing I can think of replacing the ECU. I just have to make sure I get the right ECU. Updated version - california emission - I don't know. Guess I will give the VIN to Acura dealer and they can tell me which ECU to get.

Frustrating!! I really thought I fixed this problem!!!

 

post a video of the problem. It will be a little easier to get some help diagnosing. It could be the motor mount, or something has come loose that wasn’t torqued properly.

 

I will try and get a video.

Yesterday I drive around, put car in park, and it was fine.
Later I drive around some more, put car in park, and the idle goes up and down, revs up and down. I then put car into reverse then quickly back into park, and the idle is fine.
Sometimes when it revs up and down, I will put the AC on and off and it makes the revving stop. Sometimes it doesn't.
Not sure why this isnt a constant problem. What makes it intermittent? Why does going in and out of park or turning the AC on and off sometimes help?
Makes no sense.
There is a local auto electric specialist that I may have look at it but he wants $150 per hour to diagnose. Maybe there is a short somewhere? But why was everything perfect for 2 weeks after I replaced IACV and throttle body?
I may just buy a used ECM and have Acura install/program. But if the ECU is bad why aren't there other ECU related problems?
None of this makes any sense. If the AC wasn't cold and if the engine and transmission weren't strong, I would probably get a newer car. But not having a car payment is nice.

Thanks.

 

I may have missed it, but did you check the engine mounts? They are vacuum controlled and perhaps allowing a leak when the engine sits in different positions (parked at different slopes)

 

I am not sure how to check or what to specifically look for when it comes to mounts. my limited understanding is that there is a large mount not far from radiator (lower area) and it has a vacuum line attached to it. Maybe i can purchase a new vacuum line (looks like a thin rubber hose) . My understanding is that this is the only mount with a vacuum line.

 

There’s a vacuum controlled mount in the rear as well, and a pain to get to; so it’s often overlooked.

Some people check by clamping the hose that runs from the intake manifold to the mount control solenoid (not the same as the evap purge control solenoid) and observing.

Definitive test is to attach a vacuum gauge to the hose running to each mount applying a small amount of vacuum and observing any loss in vacuum over a few minutes time.