My 04AT when cruising in city around 35 to 55mph light throttle about 2.5k the car will drop and surge back intermitantly. It feels just like the ECU is going into closed loop. Suspect a bad TPS. The other thing is when it does this the RPMs loap about 1k so 2k cruis instant drop to 1k and bounce back to 2k. At faster speeds 60+ this does no ocure.

Normal closed loop functionality would not efect the RPM guage unless the ECU controlls it on the 8. Second thing is when I was working on it other day I never noticed a TPS unless it is heald in with the electric TB.

So what do you think my problem is?

My dealer is out of the ?, they are a bunch of fumbaling turd monkeys.

 

You should be getting a check engine light if that's the case. Any other dealers you can bring it to. They could at least plug in the diagnostic computer and see any codes. Even F.T.M.s should be able to handle that.

 

Sounds more like a transmission issue to me with the auto 'box, like iti is hunting between gears. As if it was right on the cusp, and there was not enough hysteresis. If you did some logging with a good scan tool (did someone say sCANalyser?), you would be able to see what the behaviour of the sensors etc. are doing.

Cheers,
Hymee