Hey Guys,

I just finished my engine rebuild and turned the car on for the first time today. It ran good for a few minutes but after the engine is warm the car start revving itself on its own.

I cleaned MAP sensor and IAC valve and its still revving itself. I think My throttle body is pretty clean last time I looked at it. What do you guys think it might be?

I'm planning to replace all the vacuum lines next weekend and see if that will fix it... Does anyone have any experience on this?

 

A major vac leak will cause that also. Check for crosses lines.

 

Billman,

Do you think my timing might be off? When the timing is off will the engine rev itself? Just curious...

 

No, unfortunately timing is controlled by the computer, there is no adjustment possible.

 

Started after it was warm? Coolant hoses near the throttle body connected/leaking? If coolant is leaking out of the hoses around the throttle body the car will have trouble knowing when to "idle down" and start revving up to 2k and back down many many times on its own. Ask me how I found that out.

 

This hose right here:



Sprung a leak on my car not too long ago. Once it was warm, the idle would rev up to 2k, back down, back up, back down etc until it was fixed.

 

This also sounds like a faulty tps sensor, I'd start with that

 

A follow-up by OP would be nice. Kinda common issue in older cars, with hardening hoses.

Like hardening arteries, in us old geeks.

 

After cleaning my IACV I would have this issue on initial startup. After driving the car around town and ripping it on the highway to WOT in a few gears it would stop. I have a feeling it had something to do with idle relearn.

To be more specific mine would bounce from 1k - 3k

 

I'm planning to replace all the vacuum lines and check the TPS this Saturday. I will follow up on this thread if I find anything.

I tested the Cam Position Sensors with two multimeter. One of the multimeter read 3.11 (ohms) and my other multimeter read 0.96-0.98 (Ohms). So I'm not quite sure if my cam sensors are bad.

Has anybody had the same experience with cam sensors? I think the manual says if the resistance is not between 1.845-2.45 (ohms) they should be replaced?