any other ideas? IACV
 

okay... so.....

I have put on 3 new iacv's and my car was still reving up and droping in idle... i also checked for vac leaks and it seems to be neither i have broguht it rto 2 shops they dont know wats going on.. so what else could this be.. My next step is taking of the intake manifold and cleaning that up cause i chacked my intake and it was like coated in mud/dirt(cold air ) so it makes sense that some of that dirt made its way up there.. but i would still like opinions on this.. i ahve also drained the coolent and re-filled.

also can this be caused by a stretched throtle cable?

I remember finding a small crack on the bottom of a plenum (had some carbon built up around it) on the intake manifold that was causing a bad idle, covered it with some JB weld and it was good to go. I don't think it could be your throttle cable either.

crack in the exhaust manifold which is sending a bad signal from your o2 sensor. just have a quick peek under the heat shield Honda exhaust manifold always crack

Try changing your thermostat, that cause the same problem in my last civic.

dont think its exhaust manifold got DC headers, thermostat u say eh?? that could really do this? whe n i start the car it revs like 4000-5000 for like 8seconds

A thermostat is not going to cause your idle to drop.

Bring it to my shop. I'll find the problem.

thats quite the way out there... and the cash flow has slowly rained out untill payday

Understandable. Just trying to save you a few bucks. Don't bother replacing the thermostat (unless it actually fails a test) but this is not causing your idle issue.

if i unplug the iacv and it stops reving up and down is that defently the problem or can it be something controlling that?