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Neal, Dodge Mechanic
Category: Dodge
Satisfied Customers: 8351
Experience:  30 years experience in Dodge Chrysler and Plymouth
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99 Dodge Ram 2500: Cummins Diesel..The throttle..Truck starts..idles

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I own a 99 Dodge Ram 2500 with a 24 valve Cummins Diesel. The throttle has gone out and I'm trying to trace the problem.
Truck starts and idles.
Press accelerator and nothing happens. pedal springs back and is not stuck.
What if anything can I check and fix.
I would prefer driving my truck to my mechanic rather than having to get it towed.

Welcome to JustAnswer, I'm Neal and I am here to assist you.

Please feel free to ask follow up questions, it is part of the process.


That may be your TPS, here is some info. But first try disconnecting the batteries for 10 minutes and see if that resets it. It might start working and you can get it to your mechanic.


The Accelerator Pedal Position Sensor (APPS) is a linear potentiometer. It provides the Engine Control Module (ECM) with a DC voltage signal proportional to the angle, or position of the accelerator pedal. In previous model years, this part was known as the Throttle Position Sensor (TPS).

Diesel engines used in previous model years used a mechanical cable between the accelerator pedal and the TPS lever. Linkage and bellcranks between the TPS cable lever and the fuel injection pump were also used. Although the cable has been retained with the APPS, the linkage and bellcranks between the cable lever and the fuel injection pump are no longer used.


The APPS assembly is located at the top-left-front of the engine. A plastic cover is used to cover the assembly. The actual sensor is located behind its mounting bracket.

The APPS is serviced (replaced) as one assembly including the lever, brackets and sensor. The APPS is calibrated and permanently positioned to its mounting bracket.

CAUTION: Do not attempt to remove sensor from its mounting bracket as electronic calibration will be destroyed (sensor-to-bracket mounting screws are permanently attached). Two accelerator lever set screws are used to position lever. Do not attempt to alter positions of these set screws as electronic calibration will be destroyed.

Neal and 3 other Dodge Specialists are ready to help you
Customer: replied 6 years ago.
Thanks for your help. Sounds like the problem I'm having.
You're welcome. Should not be to bad to fix.
Customer: replied 6 years ago.
Hi Neal

I have a follow up question. Removing the battery connections did reset the APPS. I was waiting for a convenient timeuntil I could see my mechanic who is 45 miles away. But the problem keeps coming back so that each day I have had to do the process all over again.

To reduce the problem location search time, what areas should be checked that's bad.... or is it the APPS sensor itself that is bad? Maybe it's a dumb question but .... that's why I'm not the mechanic :)
Without a scan tool, my best guess is that it is the apps. But of course that needs to be confirmed.
Neal and 3 other Dodge Specialists are ready to help you