01 Durango slt 4.7l idle races or low idles on its own after driving on the highway for an hour or so and at the same time the transmission just stopped working then would engage but wouldn't upshift except occasionally all the while the engine is doing whatever it wants without anyone even touching the pedal. Anybody?? Ideas????? Never seen anything like it in all my years

 

Bad TPS? Bad battery connection?

 

The tps is something that came up quite a bit on my internet searches .... it's my gf's truck and I just spoke to her and she said that after letting it sit a few hours she got in it to move it and it started fine she put it in drive and it seemed to respond ok but when she put it in reverse to back it up she said the engine started racing to like 3500rpm's and she had to practically stand on the brakes to keep it from taking off and that the brakes could hardly keep the rear tires from turning

 

Had to move the truck myself yesterday...... got in and as soon as I started it it was just above 2000 rpm's .... let it run for a minute and when it didn't back down on its own I gave the accelerator pedal a tap to see if that would bring it down and instead the engine stuck at about 3300 rpm. Does this sound even remotely familiar to anyone?????

 

I'd verify that the throttle body itself isn't sticking open. Also if you have a OBD reader you should be able to see the throttle position sensor value.

 

Thank you .... that makes sense .....I will keep you posted!