My idle is all wonky. Sits at 500rpm, then after being driven, sometimes it'll bounce between 1500 to 2500. Back and forth, back and forth. I was told it's caused by a faulty idle air control valve. Can I clean it out somehow or is it just something I have to replace?

 

stock motor/ECU?? more info req'd here

 

Yes.

Stock motor. Stock ECU. I/H/E.

Sorry.

 

Try pulling the TPS sensor, adjust the throttle screw to stock idle, reset the ecu and see what kind of results you get. Several friends have had the same problem and this has fixed it.

 

you also might need a new throttle body gaskette

 

Yes you can clean it. I would suggest checking it first. Tell us if there are any DTC codes. if there is, it should be a 14 I believe.

to check pull off the harness on the iacv when the car is idleing at full operating temp. if the rpm does not fluctuate or stall, its bad or clogged. Then clean out with carb cleaner and retest. if that does not work, just replace it. Also bleed the cooling system of air pockets. that can create fuzzyness in idle.

vacume leak check can also be helpful. spray carb cleaner around areas that vacume lines are. if you spray an area and there is idle fluctuation, there is your area of concern.

 

Thanks for the advice.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by intekragsr &raquo;</TD></TR><TR><TD CLASS="quote">Yes you can clean it. I would suggest checking it first. Tell us if there are any DTC codes. if there is, it should be a 14 I believe.

to check pull off the harness on the iacv when the car is idleing at full operating temp. if the rpm does not fluctuate or stall, its bad or clogged. Then clean out with carb cleaner and retest. if that does not work, just replace it. Also bleed the cooling system of air pockets. that can create fuzzyness in idle.
</TD></TR></TABLE>

So I ran the car till it was warm and the fan turned on. I pulled the plug in the back of the IAC, the RPMs dropped but only very slightly. Maybe 100rpm. The car still ran fine. The check engine light came on sure enough. The code was 14 as expected. I have it out of my car. To clean it, do I just spray it with the Carb cleaner/alcohol and hope for the best? Or is there a way to test it before I put it back in the car?

 

similar probs here...bump

 

I dont believe there is any way to test it while its off the car. Just spray the living hell out of it with carb cleaner till no more brown gunk comes out. Make sure to clean the screen well too. If that doesnt work, i guess just replace it. Mine got fixed with the cleaner.

 

Put the IAC valve back in last night after a thorough cleaning. Burped the rad fluid and reset the ECU. Same problem. Did the test again. RPMs only dropped slightly and computer still throws the 14 code. Guess now need to buy an IAC valve.

 

I'm going to try pulling the TPS sensor tonight and resetting the ecu to see what happens. The throttle body gasket still looks really clean. Is there anyway to test it?

 

So to further back up my belief that Type Rs run better when you pound on them - the motor seems to have fixed itself. Last night I took it to the track, about 2 1/2 hours away from my house. Then I pound the living hell out of it for like 4 hours on the track. I was doing like 20 minute hot laps. When I go into the pits, sometimes it fluxuated sometimes it didn't. But when it did, it wasn't as drastic as before. Like only 500 rmp up and down. Then somewhere, somehow it just stopped and idled normally - a little on the low side - 600rmp - but no fluxuations. Anyone ever heard of gremilins in a car that run around the engine bay while racing that fix stuff?

 

There are a lot of things that can cause a fluctuating idle: Timing, Fuel, IACV, TPS misalignment, etc...it's often difficult to gauge what the cause is...firgure out what you have changed, and then change it back to see if the problem goes away.

Also, when adjusting your idle, you need to do this through the ECU, the ECU has a target idle that it will try to maintain, and if you screw with it, it will also cause idle problems.

Here is a page that might help:
http://www.hondata.com/techidle.html

it pertains to Hondata specifically, but it also describes the problem you're having, and how to more or less fix it in a more general sense, or at least enough to narrow down possible causes.

I wouldn't replace your IACV, more than likely it's not bad, not if the problem is intermitent.

Good luck,
Aj