Hello, I'm new to the forum. I've lurked from time to time for info.
I've got a problem that I hoping someone can help me with.
A friend just picked up a 99 2.3cl with an idle problem. I'll give what I've seen so far. Here Goes:
-On cold start up the idle revs high [1100+ rpms] but steady [while in park].
-As soon as it warms up [a couple of minutes] it surges [1100 to 1800 +/-].
- Put it in gear [it's an Automatic] it's goes high and steady for the most time. Sometimes surging at a traffic light but usually high & steady in gear.
-The previous owner must of spent a couple of bucks trying to fix this.
-The throttle body was removed & seems to have been cleaned,reinstalled with a new gasket.
- The following parts have replaced :
IAC, TPS, MAP.

There are no codes, no check engine light. Codes might of been cleared before he bought it. But can't get to set a code.

I checked for
- vacume leaks
- the throttle & cruise cables adjustments.
- The coolant sensor reads correct static cold & at running temp.
- Cooling sys. is not air bound
- No change with A/C on or off.
- " " steering maxed to 1 side.
- Battery & charge sys. is up to par.
- all above is good.
I haven't checked wiring yet. But , I don't think thats it. I'm leaning towards ECM.

If anyone can help it would be greatly appreciated! I hope that someone has come up with this before.

Either way, Thanks for taking the time to read this, Johnny

 

did u smoke test the car to see if there were any leaks anywhere possibly? looks like you covered alot of bases already. Usually that problem has to do with the IACV in the throttle body but it seems that yours has already been replaced

 

I don't have access to a smoke machine. But I did spray it throughout the intake & vacume lines. I also tried restricting the IAC port & then the Throttlebody. I had no improvement.I think I'm going to pull the throttle body myself & have look. Another concern is that all the sensors have been replaced with aftermarket parts rather than Oem. I'm not really schooled with Acura/Honda. Could this be something that I should be concerned with?
Thanks for reply DaIn

 

Try seafoaming the car. Might help with whatever carbon buildups are present. A lot of people say idle smoothens a couple days after seamoaning. Try that. Other than than it could be a retarted voltage. issue anywhere.

 

Thanks for your input Supra. I don't think that would help. Reason being, I forgot mension that if unplug 2 or more sensors putting ecm into limp mode the idle steadies . but Is high. So, I'm thinking the ECM is trying to compansate for a problem [most probable] or the ECM is failing [long shot]. thanks again

 

Still seafoam wouldn't hurt. Try that ground upgrade. Blackack knows what I'm talkin about. It smooths idle.

 

Case Cracked, I started from sqaure one. I check everything over again, including all the work done by the previous owners mechanic. Everything checked out. So I tried replacing the aftermarket{new} IAC with an OEM. Which by the way was $12 cheaper. Bingo! Problem solved.
THanks for your help guys.