Engine/Transmission (1998.5 - 2002) HELP!! Truck Bucks & Snorts, whats the deal???

[jrandol]

Ok I am really confused here. I re-hooked up my Blue Chip FMS box on Friday while I changed to a HX35 turbo (very nice upgrade from the stock HY) and all was good that evening. Saturday took the truck out and now even with minor fueling added the truck bucks and surges. I was first inclined to think I had toasted my VP44 with low fuel pressure but if I turn off the fueling on the box and jump into it WOT from a stop or rolling and it has no problems what so ever. The Low fuel pressure light normally comes on if I try anything over 25% fueling so I dont go there until I can do the pusher pump conversion. The box shows its adding the fueling and the VP44 Duty Cycle rating seems normal but when you step into it it stumbles all over itself and cuts out. So here are my trouble shooting thoughts:



1. The Fuel Pressure sending unit went south and I do have fuel pressure problems (failed LP) and I did fry the VP. What contradicts this is the fact that if I turn off the fueling box all is good.



2. I have a loose connection between the Blue Chip Pump Cover, the box, and the VP44



3. Something is screwed up in the Blue Chip box.



4. APPS sensor or Cam sensor has gone bad. (Currently check engine light is not on. )





Anyone please lend a helping hand here, my boy is sick and I need to find a solution.

 

[Sticks]

Bummer. You were my parallel ego that gets to play, and now you have issues.



Thinking like it's a gasser, it sounds like timing, coils, too much fuel/air, not enough fuel/air. The principles are the same for the diesel (except for the coils) so we cross check the symptoms.



Does your truck smoke when he stumbles?



Have you verified the fuel pressure with a second gauge?



How long since your fuel filter change?



All your turbo hoses have a good seal?



All your after market power connections are good and clean?



Have you made your sacrifice to the diesel gods?



Straight up, it sounds like there is an issue with the FMS or the pump cover. I don't know if the MAP and IAT sensors would have anything to do with this, but worth checking. Same with the crank sensor.

 

[jrandol]

Sticks you crack me up man!



I talked with Chip @ Blue Chip Diesel today and we came up with a few possible solutions, I will give them a try tonight. Chip is one heckuva nice guy and knows his stuff! Got a feeling it is bad connections to the Pump.





Jeff

 

[Sticks]

Let us know how it goes. Hopefully no money out of your pocket to correct the problem.