Archived calling all experts help!

[libertyram]

I have a problem that I have been fighting for 6 months on my 2001 3500. At random times the fuel pedal goes dead. It is just like you let up off the throttle. I have had it to the dealer twice and they thought it was fixed and it seemed to be for 2 months but now is back. It will go away for a time then comes back. I have changed the apps, both fuel pumps (vp44 and lift) and alternator and installed a filter on the apps line for the PCM. The dealer is out of ideas. The real crazy thing is that there are no codes thrown. The dealers scan tool reports that when it happens the ECM thinks that there is no load on the engine. Does anybody know what the Cummins ECM uses to determine the engine load? I cannot continue just to throw money at this problem. I need some ideas please!

 

[FourBarR]

have they thought of wiring problem? I would be checking all the connections between ,pcm,ecm,vp44. and all the ground and battery connections. loose or corroded contacts cause lots of problems with these trucks. good luck.

 

[litespeed]

What about grounds from engine to frame (braided), engine to cab and frame to cab?



I had a very similar problem on a Chevy 6. 5 (piece of &@#!) a couple years ago... .



I also had the exact same problem on a VW Passat TDI! The injection pump on that car bears a striking resemblance to the VP.



You will be surprised how many grounds there are when you start looking... .



Mine are corroded now and I have been neglecting the problem... .



Remove, clean, remove corrosion and re-install with dilectric grease.



AJ

 

[libertyram]

I have been through all the grounds and even added extra grounding. I have also disconnected all the connectors involved and they all look fine. But keep the suggestions comming.



Thanks

 

[Missouri Mule]

I thought dead pedal (idle only) was sympton of ECM going.

 

[mberry]

MAP sensor.

 

[libertyram]

After consulting with a Cummins rep. I have the truck running again. He suggested that I check my fuel pressure one more time. Low and behold there was none from the lift pump. Now I am really peeved. After my second factory pump gave out I installed a FASS. It would not run until I removed one of the brushes and reinstalled it then it took off. I guess that we are doomed to lift pump issues on these trucks no matter what we use. The aggravating thing is that the dealer did not think of this (guess they thought a new FASS had to be good too). The moral of this story is to have a FUEL pressure gauge (ordered one yesterday). Thanks for the reply's.

 

[GWedekind]

The moral of this story is to have a FUEL pressure gauge (ordered one yesterday). Thanks for the reply's.

I agree!!!!!!!!!!!!