hello all

well SOMETIMES when the engine is cold and it warms up the rpms moving up and down
for example they move 100 up and 100 down
when th engine warms up its ok but even if i drive it with the engine cold it still runs fine
so whats the problem if theres any
thanks
my car has 118,000miles

 

It is probably something in your cold idle system, I wouldn't worry a about it too much. If it really bugs you you can check the operation of your IAC.

 

what does IAC mean and how do i check its operation
how much is a new valve cause i dont have any tools to check it so my mechanic will have to do it .....

 

If you don't have the tools yourself then I wouldn't bother with it. It is not harming the car in any way, but if it really bothers you then take it to your mechanic and tell him to check operation of your idle air control. If he doesn't know what that is then find a different mechanic.

 

This idle hunting is sometimes due to a leaking fast idle valve (FIV). The FIV allows extra air into the intake during cold starts and should close as the engine warms up. If it leaks, the normal idle control that the ECU tries accomplish with the IACV is impossible. I don't know which model you have, but a quick check to rule in/out the FIV would be to pinch off the air tube feeding it.

 

rule in/out the FIV would be to pinch off the air tube feeding it.

wat tube? i have an intake ..
thajks