i have a 2001 chevy cavalier 2.2 ohv it has been a great car but for the past 6 months the car has had a wierd hesitatation stumble buck dont know what to call it but noo codes i replaced the throttle position sensor did a fuel injection service plugs wires and coil and still it does it evry couple weeks just once i have an after market intake and header i thought maybe it could be the o2 sensor cause its been relocated to the down pipe i do notice that my car is running very hot just not going to the max (fans cool it back off im just soo confused any advise will help oh i have to tell you what its doin first its basicly when coastin at lower speeds almost stopped and than stepping on the gas its starts jumpin than comes out it like nothings wrong i do see the trac off light come on than go off sometimes but not when the problem is occuring may it could be a solenoid on the trans or IAT sensor or coolant temp sensor just wish i knew please help thanks