Hesitation

[wayne_ford]

I noticed when the car is cold, it runs great (no hesitation). When it warms up, sometimes it doesn't seem to go (hesitates). The car is a '92 MTX with 139k on it. Any suggestions?

 

[orlando]

I suggest you change the air by-pass valve and gasket.

Orlando

 

[wayne_ford]

Where is that located and how much is it?

Thanks

 

[sdpatt]

Sounds more to me like the throttle position sensor, but I would need more examples to be sure. The IAC valve only controls the engine when the throttle is closed. It wouldn't have any affect on the engine during part throttle acceleration.

 

[luigisho]

Why not split the difference and clean the iac and change the throttle position sensor?hehe

 

[wayne_ford]

Thanks for the advice. When I'm in gear and press down further on the gas is when it does it. It seems to me that once it warms up, its running rich. Could it be the O2 sensors? Could my Cats be going bad? I know there is a small exhaust leak somewhere on the "Y" pipe.