Engine/Transmission (1998.5 - 2002) Priming issue on 2001

[NKenny]

A few months back I wen through the replacement of a VP44 on my 2001. I started with the FASS pump, then a new VP44, etc. Once the pump was in, the idle was a little rough and I had dead spots at 1500-1700 rpm and again at ~3000rpm. Took the pump out, had it tested and it cleared. I then went and replaced the injectors since the truck was near 180,000 miles. In the process, I developed a priming issue, where the truck will need the starter bumped in order to start if it has been sitting for a while.



I have checked and rechecked every fuel fitting I can think of and it still loses prime. I even went back to the original fuel pump thinking that maybe the FASS set-up had a bad check valve. I haven't conqured this issue. Any suggestions.



BTW, the misses seemed to clear-up with a replaced IAT sensor. I got this thought when I realized that the truck idled very well until warmed-up.



Thank you!

 

[NKenny]

Also, how do you make the truck profile show-up on posts?



The truck in question is a 2001 Quad-Cab Shortbox, 4x4, 6-speed.

 

[blacksheepdiesel]

Did you replace the relief valve on the VP?



Trent

 

[NKenny]

Yes. It was my understanding that the new valve was pretty important, although I don't know enough about the pump to know why.

 

[SpicyJam]

The prime you are talking about is normal for the 24v. When you first hit the key psi jumps up and while you wait to start pressure will drop before starting. If you bump the starter the pump will run for awhile then shut off until truck is running.

Sorry I just re-read the thread. When you changed injectors did you replace the O-rings on the cross over tubes? If they are tore the prime will be lost. Or if the end of the cross over tube is damaged.

 

[NoSeeUm]

Also, how do you make the truck profile show-up on posts?



The truck in question is a 2001 Quad-Cab Shortbox, 4x4, 6-speed.

User Control Panel -----> Edit Signature



Thats what I used.



Jim

 

[EGaskamp]

Is the relief valve under that big bolt thats directly to the left of the VP fuel inlet?

 

[NKenny]

Thanks. Replaced the O-rings on the cross-over this weekend and the priming problem is gone. One was torn and the 5 others were very dry.



A friend has been driving the truck for the past month and as is typical with my operation, delaying the fix ended up costing me a starter too.