Driving at highway speeds my rpm's increase about 200 constantly. The only way i really noticed was a change in the exhaust tone really has no affect on the driveability in any way i just know this isn;t normal. Any idea what would cause this?

 

auto trans? try the tps, common problem. cheap and easy to replace. just my 2 cents worth.

 

i had the same problem a few years ago... it was the tps.

 

I have recently had the same problem, I changed the tps, and it did no good, come to find out my transmission was slipping (auto) and the torque convertor was going out.

 

tps? what is that

 

throttle position sensor.

 

The rpm's on my 2001 4.7L started surging on the way home the other night while driving around 65 mph and it brought up the CEL. When I turned the O/D the problem got better.

After reading this thread I'm going to replace the TPS this morning (and get the CEL read), but now it sounds like it could be a torque converter problem?

FWIW, on cold starts in the morning the rpms fluctuate up and down quite a bit for the first minute or so, which is also what makes me suspect the TPS.

Thoughts?


Edit: Separate issue, but maybe related... has an over-heating problem while driving in town (low speeds) or idling, but highway driving is fine. The day before this surging/CEL issue happened I noticed a slight "ting-ting-ting" after shutdown from underneath the bed of the truck. Was there the night the CEL came on too. Sounds like something's pretty hot. The tranny has been replaced already (about 20k mi ago- @ 73k now).