Update:

It is possible for a motor to rev to 5000 with the throttle plate closed, if, there isn't a vacuum leak somewhere?



The idle on my 90 accord surges from 1000 - 3000. Car is all stock. Temperature isn't a factor. No cel.

Help me out with some suggestions.

So far I have replaced all the vacuum lines, the iacv, fitv, and the map sensor. And disconnected the egr and charcoal canister.

I haven't checked the alternator.

Anything I'm missing?

 

have you taken off the throttle body yet? I would degrease the **** out of it and check the tps voltage



also give the plenum a good cleaning has well and just wipe it clean




I like carb cleaner or brake cleaner for the job



Also if there is alot of build up on the throttle bodt plate area take a piece of sand paper and clean the plate and tb. Then slam the shot out of the throttle rotor to make sure you have a perfect seal


loosen up the screws that hold the throttle plate in place before doing this



Throttle body should be liquid tight.

 

fast idle control valve its the only thing that makes them do it period

 

I blocked off all of the vacuum ports on the manifold and it still does it....

SO, I think that it is a vacuum leak.

 

blled coolant has well

 

thats the problem then the ficv is need by the ecu to regulate the idle circuit

 

The coolant has been bleed.

ficv=?
I have tried 3 different iacv's.

 

well its not that then



what about the egr port? Those things get very clogged and could cause some issues

 

I haven't ever heard of an egr producing basically the same surging problem as the fitv...but I will deffinitly take it off and clean it up.

Currently its 6 degrees and the wind is blowing.

 

just thinking out loud. Anytime I do h22 swaps thats what I do has the egr ports get uber clogged up and well its worth a try