Car is reving nonstop?

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raidmax

New Member
When I start my car it revs to about 3000 rpms then goes down to 1100 rpms..... and keeps doing this over and over?

I've checked all the vac lines and it looks like everything is pluged up in the engine bay...
 
There has got to be a vac leak somewhere... 3000 is pretty high. Check all hoses, PCV valve, and gaskets. Also, the FITV (fast idle thermo valve) could be way out...
 
hit it with a hamer and light the bitch on fire


sounds like the idle controle, double check vac lines, and check them again. almost positive that is it. same thing with my old civic. never go to 3000 though
 
yeah my car did that to and it was my intake air control valve. on my car its located by the throttle postion sensor on the intake manifold.
 
I just replaced all the vac lines about a week ago. I'll check and see if I have any leaks tomorrow.
 
Check your coolant level. I use to have that problem when my radiator was leaking. It would rev like that when the coolant was low.
 
Can somebody tell me where the Air Idle Control Valve and the fast idle thermo valve is located? I've searched google and searched through my Chilton Repair Manual and cant figure out where they are.

I have a h22a JDM swap in my prelude... stock manifold and tb.
 
bump....

can somebody tell me where the Air Idle Control Valve and the fast idle thermo valve is? JDM h22a motor and stock intake mani.

**Edit
I took a hammer and started beating the shit out of everything under the hood. I then drove my car around the neighborhood (really fast) and now it doesnt rev anymore. It idles now around 1400 rpms.
 
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coolant level is good.... my car is overheating. I've replaced the thermostat, but didnt help anything.

I can feal fluid in the radiator feed hose and the return hose. I can take off the hose from the top of radiator to the radiator resivore.... and "steam" is coming out of the hose. It doesnt seem like any fluid is leaving the resivore and circulating in the engine.

...after I beat the hell out of everything under my hood, it now only has the rev problem untill it warms up. Then it idles fine @ about 1300 rpms. When I first start it, it revs to about 2500 rpms then down to 1000 rpms and repeats.
 
similar problem on my car, it gets better as it warms up.
 
Where is the fast idle thermo valve and air idle control valve?

JDM h22a /w stock intake manifold.

Problem not solved.... my prelude still idles up to about 2500 rpms then down to 1200 rpms over and over.
 
Take the throttle body off the car, look at the side that would have faced the firewall, you should see two screws holding a plate on. Unscrew them and pull the plate off. Take a couple screwdrivers and screw the plastic thing in there down, reassemble and see if that fixes the reving problem. I think you have an air bubble as well which is causing the thing to overheat, you'll have to try and get it out or take it to a shop that has a special tool for getting them out. Just to let you know the air idle control valve is on the front of the intake manifold and has a coolant line running to it, if this is the problem its cause of the air bubble.
 
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