the car is reving slowly on its own to about 2k (five or take .5). its not constant, but its getting worse. also, when it decides to do it, i can rev a little and it will just stick at the peak of the rev if its between 2-3k. it started at my last fill-up, so.... really bad gas? or is my tps or something fouled?

 

could be the TPS or the IAC

 

Yea check the TPS and IAC(idle air control) valve. You might need to clean it. If so, heres directions for cleaning your IAC. http://www.muscularmustangs.com/iac.php

 

Could also be a vacuum leak somewhere in the system.

 

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