Jump to content

Recommended Posts

Posted

Hi there, recently my comanche will start reving high randomly. Doesn't happen often but once and a while the RPMS will climb and I'll have to shut the truck off and restart then goes back to normal. Is it an Air filter issue or a sensor of some kind? Any help greatly appreciated.

 

 

Posted

Well. We don't exactly know what engine you have. I'll assume it's a 4.0 I had a issue with high revs. I would start my truck and it would be around 1000rpms and I would guess it would go up to around 1200 for cranking. If it is indeed a 4.0 you could try cleaning your butterfly valve in your throttle body. It may be sticking open or not closing all the way. It could be your throttle position sensor or idle air control valve. Me and the guy working on the truck chased this for a while so I just threw a new TPS, IAC and went ahead and did a new O2 sensor and she purrs like a kitten now. It also wouldn't hurt to check for vacuum leaks, loose vacuum hoses or disconnected ones

Posted

We do need to know what engine you have.

That said, header bolts are known for being loose on the 4.0L.  If you have a 4.0, make sure they are all tight.  These are the nuts and bolts that hold the intake and exhaust to the head.  You may even find a few missing.

Posted

I ended up just cleaning the throttle body and AFS as they were both gunked up pretty bad. Hopefully that will solve the problem.

I'm working on a 89 4.0 Pioneer Manual 4x4

 

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...