hallio217

I bought the truck a month ago and I went right to work to figure out my fuel supply situation. Thanks to this website, I figured out that I had the lift pump in the tank put in by Dodge: https://www.dieseltruckresource.com/...d.php?t=315776

So I went ahead and installed a Factory Replacement Raptor Pump at the engine block. I didnt want to have to drop the tank to remove the lift pump in there , so I wired a switch to the relay that controls the rear pump and I was able to run both lift pumps simultaneously. Using a pressure test gauge I found that I had 24 psi at idle, so I figured that it would have more than enough pressure at WOT, but never tested this and had no pressure gauge in the truck (this was my fatal flaw) . I drove about 400 miles this way, no problems. The past few days I was hauling 3000lb loads of concrete up steep grades. Today, after dumping the final load, I pull away and without any hesitation or rough running the motor just dies and I coast to a stop. The only thing out of ordinary that I noticed was earlier in the day some wavering in the RPM idle. Other than that, there were no signs.

The VP44 is original so lasting 166000 miles isnt that bad.

I just wanted to share that info with you all. I will now start my research on injector pump replacement.

My two takeaways:
1. DONT RUN THE TRUCK WITHOUT A FUEL PRESSURE GAUGE
2. THE VP44 GIVES VERY LITTLE WARNING BEFORE IT GOES

Finally, I still love this truck, just need to supply the injector pump with good pressure.

Lary Ellis (Top)

Too much pressure is also hard on the VP44, flow is the key and that is why you can't pull through another pump. You need to use a draw straw or a fuel sump type set up so you get lots of flow at the right pressure

BigIron70

Good info here on fuel pressure and the vp44

http://articles.mopar1973man.com/2nd...njection-pumps

hallio217

Ok. I will definitely get the draw straw kit and remove the original in-tank lift pump

hallio217

I will be sure to read that, thanks for sharing!

SIXSLUG

I would also check codes, you may have a bad ECM. I thought my vp gave it up at 98K, but it was a faulty ECM...

Just sayin...

At least you have nice weather to work on it in...I'm from Fallbrook!

DIESELWRKS

another source to look up to see what you exactly have wrong.

http://www.bluechipdiesel.com/vp44diagnostichelp.html

and

http://www.bluechipdiesel.com/lift_p...agnostics.html

hallio217

I checked for codes using the ignition on-off cycle and all I got was "P-Done".

DIESELWRKS

you can also look on moparman74's website for good info on electrical gremlins. ECM issues too. my ECM took a dump not to long ago but I had about a million codes because my Everything registered a error due to not getting enough volts etc. clean up all wires, grounds post. make sure you have good batteries. double check for any new dark wet spots for leaks.
do you have any power? cab lights etc. when you turn your key on is there a error message or weird reading up top where your MPG/compass reader is?
can you even bump your fuel pump by turning the ignition to just bump it without starting the truck. This will cycle the fuel pump to run for 30-40 seconds. any fuel reaching the injectors. need a 3/4 wrench to take the injector line off #1,3,5 just enough to see if fuel is reaching. it may take 3-4 bumps with the fuel pump to do this.
you may already have tried this or know this to try.

hallio217

Good news. I took my truck to Injection Diesel in Colton. They did a diagnosis and found that the injection pump was not the problem. All it took was removing the in tank pump, like I should have done before! As it turns out, the in-tank pump was resisting the fuel that the FRRP was trying to pull through.

SIXSLUG

Good deal!