I am having a idling problem with my D15 91 civic standard for a while now. Do not have the problem during the winter time, but now that it is getting quite a bit warmer out her in the midwest, the car will idle high and keep jumping from the normal idle position (500-600rpm) to a higher idle (probably near 1000rpm) and then will repeat that when I am at a dead stop, but is fine when I am driving. The weird thing is the that coolant temp gauge reads only about 40-50% on the gauge rather then being higher like it should be if overheating enough to cause the idling issue. I have not yet looked at it and thought I would try and see if anyone here would know the direct problem before I go about looking at everything else.

Thanks.

 

See if you are throwing a code on the ECU. Mine does this too and its reading code 14 - idle air control valve. Mine is pretty intermittant though which sucks.

 

Its definately an IACV (or is it EACV) problem. Basically you have to take off the part and clean it out. Do a search its been explained lots of times.

 

I have actually ran the car without the radiator cap to make sure there were not any air bubbles in the system that would be screwing around with the issue...and that checkked out ok. I then took it for a drive around the block and it was doing the same thing...tends to idle very high after I have it in gear and let it go into nutrual for the stop...it will normally idle high for over a minute some times...After it was doing that I pulled the IACV plug to see if that might have been the issue and when I pulled that it actually made the cars idle pulse very high (it normally does the same thing even when the plug is on there and I am driving it around on a hot day and come to a complete stop in nutral (tends to pulse just like it was doing when I unplugged the IACV)). I am not sure what the problem could be right now. Anyone else have any ideas?

 

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