Engine/Transmission (1998.5 - 2002) Engine Dropping to Idle, Check Engine Light On

[PCrable]

I've had a strange occurance happen to me about 8 times now. I'll either be starting out from a stop or just cruising and the engine will drop to idle and the check engine light will come on. I just let up on the go pedal and push down again and the truck starts going again.



The check engine light clears itself after 3 (or maybe it's 4) times of starting the truck.



This has only been occuring since I installed my PE Comp with the pump wire pierced. I tried checking all the connections to make sure none are loose, but it it still happening every now and then. If I could catch it before the fault clears, I would like to take it to one of the auto parts stores that can read the fault code.



Anyone have any ideas on this ?



--Phil

 

[wtrenholm]

Even though the CEL goes off the code should still be stored and retrievable. It should stay in memory for at least 50 start cycles (I don't remember the exact number of start cycles that the code is erased at).



Sounds like it could be dealing with the APPS, but thats a guess at best.



HTH

Wayne

 

[Sean Flanagan]

Welcome to the world of "fly by wire". There is no mechanical connection to the injector pump from the go-pedal. Just a handful of wires connected to a rotary potentiometer which is connected the throttle cable.



It sounds like or Throttle Position Sensor (TPS), also called APPS (Accelerator Pedal Position Sensor). You probably bumped it while rootin' around in there hooking up that pump wire. It is located under the black curved plastic hood right above the injector pump. You probably had to remove the 3 bolts from it and move it off to the side to gain better access to the pump wire. (Front of cylider head on drivers side) Try unplugging and re-plugging the connector a couple of times. Be sure the ignition is off or you will set a trouble code.



Mine crapped out for no apparent reason but got replaced under warranty the dealer at about 75k miles. It is NOT a Cummins part. I tried to buy it from Cummins, but they said it is "application specific" and must be purchased at the Dodge dealer. I think the thing costs a staggering $300 or so. You cant just replace just the sensor, you have to replace the whole assembly which includes the mounting bracketry and everything.

 

[Goodwin]

mine had the same problem last week, dealer replaced the TPS sensor, and it has been fine ever since.

 

[Texas Diesel]

This from a prior post, not sure what year it referred to:



I had very similar problems this past winter/spring. After reading some other posts, I go to Cummins and got the following part #: 4002066. Called; Sensor, Position (according to my receipt). Total cost: $36. 00+Tax (Your price may vary!)



It was on the port side of the engine towards the back and the bottom. Mine was a PITA to get out... ended up breaking it.



Seemed to fix the problem though.



I have also read of some dissembling the APPS and cleaning the potentiometer, seems dirt is the problem, keep us posted