Engine revs its self after 5-10 mins of driving

MIKEESEVERN

MEMBER
2002 ROVER 25
89,000 MILES

Hey,

I've had this problem for about 3 weeks now... I turn on the engine and everything is fine to start with. It idles at about 900-1000rpm. I then drive of and doesn't matter how nicely i drive or what but after about 5-10 mins i can feel the engine judder when i take my foot of the pedal and the engine starts to slow down, when i press the pedal down again it judders again. This lets me know when the engine start going off on one!

When i come to a stop and take the car out of gear or hold the clutch down the needle revs itself, it first goes up to about 3000 then down to 1000, back up to 2500 and down to 1000 and keeps repeating this until i either turn the engine off or move off again, but as i pull of I don't need to use the gas as the engine is already at 2000 revs. When changing gear.. instead of the revs going down they go up!

When i turn the engine off then back on again it pretty much resets back to 900-1000 rpm and starts again after 5-10mins.

The car about 3 years ago had its head gasket replaced when it blew so i'm hoping its not this again.

This youtube video isn't of my car but is showing exactly what my car does.
http://www.youtube.com/watch?v=ABHM2cE3FXI

Personally i think its the Idle Air Control Valve but these can be exensive ive heard and would like other people to see if they think this is the problem.

Thanks for any help given. :)

1 Reply

JACOBANDNICKOLAS

MECHANIC
109,755 POSTS

What you have described and I watched, that is my first guess, the IAC. That is the part that is designed to maintain a smooth idle. Before replacing it, check for vacuum leaks. Also, you can remove the IAC and check to see if it is working. When you turn the key on, the pintil shold move a small amount. Check it to see if maybe it is carboned or needs cleaned.