I've fixed all the previous bugs but I still cant get my idle problem fixed. I have already replaced the throttle body because the previous one had no TPS sensor (broke off) Now to the problem


After my car warms up it will not idle (1989 CRX Si) if you arent running any accessories. For example--I can have the headlights on it will idle fine, i can have the heater on level 3 or 4 and it will idle fine, or i can have the stereo up loud (amps,subs) and it will idle fine

It will not idle when ALL of these arent running. The idle will fall to like 100-200 rpms. I have checked as many grounds as possible and I'm not getting anywhere. I unplugged the idle air control (2 pin connector) and the idle was at like 300 rpms (ran smoothly) but once I connected it back in it was bogging again (100 rpms and missing and bumbling around) I have also installed new cap,rotor,plugs,wires, etc and the alternator is a new rebuild.

Any clue guys?

 

bump

No help?

 

IACV? that contorls idle when load is on engine...that's my guess.

Thanks,
VINCE

 

My guess is the base idle is too low. Have you checked that. Warm up the engine, disconnect the IACV. it should sustain idle at around 650-750 RPM. If it will not adjust the idle screw on the top rear of the TB. Backing the screw out increases the idle. Bet thats it!!! When you have the accesories on the load dectector circuit ups the idle to around 800-1000 to help with that extra alternator load. In your case it gets the idle just up to minimums.

 

I will try that tonight but odd thing is, ive tried on two different throttle bodies. So i'm not sure what the deal is. But you are right , I have disconnected the IAC and idle does stabilize around 500 rpms or 600. Plus I read that a "bad" IAC usually affects cold idle not normal operating temp idle.

 

Just remember to disconnect the IACV when adjusting the idle screw, if not you'll be turning the screw all day w/little results. A bad IACV can effect bad idle throughout, from cold to normal.

 

How do you clean them? if it seems to be at fault

 

I am leaning more towards a bad IAC considering I turned the screw and the idle went up to about 1400 or so and it was still missing or sputtering w/out the accessories turned on.

I found one on ebay for 5 bucks, probably going to buy it

Edit: If the IAC is bad, should the idle change if i unplug it, cuz if i unplug the IAC then the idle smooths out

 

i think that if the idle smooths out with the IAC unplugged then the IAC is bad. not 100% sure though. I think the idle should stabilize at 700-800 when IAC is unplugged

 

Is it safe to drive w/out the IAC plugged in, to see how the car reacts for a day or two?