Engine/Transmission (1998.5 - 2002) APPS or TPS Not sure which....

[kdw75]

I have been having some surging and a mildly rough idle recently after the dealer replace my Crank Pos. Sensor and I am starting to think it is the TPS/APPS, not sure which I have. I have replaced this once but last time it went bad in a major way and set a light. I took the bad one though and put a meter on it, hooking to pins 3 and 4 and measured the resistance. When turning the sensor I noticed the meter readings seemed just fine on the bad one. I am starting to wonder if maybe it isn't the unit itself but maybe the wire leading to it or a bad plug that was moved when I replaced the ond one fixing the problem for a while. It has been about 50,000 miles since the last one acted up though. Any diagnosing tips would help alot.



Keith

 

[fox]

Your truck uses a APPS. The older trucks use the TPS. They do the same thing, telling the computer what your right foot is doing.

I am not an expert but I don't think a Apps can cause a rough idle problem. Injectors and injection pump are the first suspects.

Surging it most likely caused from the other issue.