Engine/Transmission (1998.5 - 2002) Strange acting engine

[jzenk]

Last week on my 400 mile vacation trip, my truck did something "new". I was pulling my 26 foot 5th wheel camper and about 100 miles from home I let off the throttle to let someone in and when I reapplied the throttle, nothing happened. The engine kept running but would only idle. There was no manifold pressure. pushing the pedal to the floor did nothing. I down shifted into 5th and it took right off. This happened several times (9 or 10). I made it to my destination and took it to a Dodge dealer who drove the truck for a couple of days and couldn't duplicate the problem. I picked it up and about half way through the 80 mile drive back to the trailer, it acted up again. The truck is a '01 2500 6 speed. It has had no fueling modifications done to it. I checked all the connections on the fuel pump etc. All wires are secure. This condition occurs whether I'm towing the trailer or running without it. No warning lights have come on and the dealer found no fault codes stored in the computer. I'm stumped. Any help would be sincerely appreciated! Thank you

 

[MCummings]

I would highly suspect a Thorttle Position sensor (TPS), rescently renamed Accelerator Pedal Position Sensor (APPS). THese are one time use units, just replace, and throw the old unit away,, non-adjustable.



My truck did about the same thing 3 years ago, it would run fine, good power, and then only idle,, sometimes pumping the pedal would bring it back to life, but usually, just waiting 5 seconds, and everything was fine and dandy. But, Mine was getting so bad that I was having to wait 5 seconds every 5 minutes. A trip to the dealer, and 3 days later, the then named TPS was replaced. No problems since then.



You can try to un-plug the negatives on both batteries, then try to start your truck twice, (this will drain all power from the PCM/ECM, and all soft-set codes will be erased) plug batteries back in, and see if it does it again.



The reason your truck only idles is becasue when the TPS/APPS sensor is out of range, the ECM defaults to the idle program, since there is no direct link to the injection pump.



Hope this helps,

Merrick Cummings Jr