Engine/Transmission (1998.5 - 2002) I require assistance

[Big_Daddy_T]

Bad problems amigos. Im driving down the highway at 80 mph and the truck stalled. It would not start. Fortunately at the speed I was traveling I was able to coast about a mile so I could get to a safe place to screw with it. I had about 5 minutes to get to work about then. After half an hour of pulling and probing still no good. The lift pump would not crank, 0 pressure. I get a lift home to grab my car and a mechanic. I go back and it fires right up. I get up to highway speed a caput. No fuel pressure will not start. I get it started drive 100 ft and caput. I crack the injector lines and no fuel. I hot wire the lift pump to run continuously . Still no fuel. I tow it home and start it up and it runs fine. I can drive it around my driveway no problem. I assume its the injector pump failing but why does the lift pump not send fuel to the injection pump after it stalls. The truck will still do 110 with no help from the boxes. It does stumble occasionally after 105 mph with the box on.



PS beat a chipped psd with propane today. He was so amazed he pulled me over to ask if I had nitrous and propane. NOPE just a bada$$ dodge

 

[Bigsaint]

Big Daddy, I doubt it's the injection pump ( could easily be wrong). Replace the lift pump and report back, that's an order .



As you have already discovered, the lift pump seldom just goes toes up completely. If the VP44 was to blame, I seriously doubt that you could have restarted the truck.



Scott W.

 

[Big_Daddy_T]

I dont understand.

I went and restarted it. Drove it 5 minutes. It ran great. I was headed home and it stalled with great fuel pressure . Then the lift pump wouldnt come on. It had great fuel pressure when it stalled. After about 5 minutes the lift pump would start working again. It would start and then die with fuel pressure. Now it gets fuel pressure and wont fire. Maybe there is a leak somewhere and air is entering the system. the lift pump is brand new. I also have a spare lift pump.

 

[Rob Thomas]

How about a fuel filter, or bad fuel? Just maybee.





Later, Rob

 

[Devildog]

Could be an intermitting electrical problem... . Check all your connectors, could also be in the lift pump.

 

[pwr2tow]

on my truck the lift pump will not run (when I bump the starter) after I have had the truck running, If I let the truck sit for a while and then bump the starter the lift pump will run it normal 25 seconds again. I discovered this after I changed a fuel filter once and the truck fired up and ran for a few second and then died. The only way I could get prime was to let the truck sit for awhile.



Sounds like your problem is something other than the lift pump, are there any trouble codes set.



Ron

 

[LSMITH]

The truck will run and run just fine with the lift pump completely DEAD. As long as the prime is not lost it will continue to run. Time and again we have seen this.



The lift pump is controlled and powered by the ECM. The FPCM in the VP is also powered and controlled by the ECM. For the truck to die suddenly and the lift pump would not work at the same time it definately sounds electrical. If you cracked the lines and cranked with the lift pump not working you should have still gotten fuel if you had not lost the prime to the injection pump from the tank. The VP will supply enough fuel with its internal pump to start and run the engine.



I would start with the fuses and relays related to the injection system and go from there. It could be the ECM itself, but that is a pretty uncommon failure. Run it some more and if it dies switch the fuses and the relay for the injection with something else. See if that helps.

 

[GiesJ]

BigDaddy -

About 6 months ago I had to have the injection pump replaced. I had been running hard on the interstate, pulled off to grab a bite to eat. I let her cool down before I shut down and then when I came back out to fire her up, nothing. I was pretty stubborn and kept cranking and eventually she fired up. Drove home nervous as heck and pulled into the front of my house so that I could change the fuel filter. Changed the filter, cracked the lines and she wouldn't start again. Did everything possible in terms of bleeding the system. No luck. Finally had to succumb to towing her down the street (with another dodge but not a diesel) to the dealer. They took a while to get to her and when they did, she fired right up.

They call me to come get her cause ain't nothin wrong and by the time I got there she wouldn't start for them. To make a long story short, 3 weeks later I got my truck back with a brand new injection pump covered under warranty. I guess the dealer had to spend quite a bit of time on the phone with DC tech support.

I hope this helps you a little bit. I have heard that the 98. 5's like we have do have more problems with the 44 than newer trucks.

Good luck,

J

 

[Big_Daddy_T]

vp44

This is my second vp44. My first failed at 28k. I have over 100k trouble free miles on the new one. When the lift pump wont pump neither will the vp44. I did get a code. I havent been able to pull it.

 

[Big_Daddy_T]

Well pucky. The old beast has a date with cummins nw. I had it towed there this afternoon. they said theyd give it a once over first thing friday. I tried all the relays and fuses first thing. I was waiting for the tow truck and for smiles I started it. It cranked one time and fired up like normal. I idled it for 10 minutes put it in gear drove it 30 ft and it stalled. Lift pump wouldnt run after it stalled. screw it. leave it to the pros. I wonder if I can talk em into the uprate reflash while its there.





P. S. HAPPY FOURTH TO ALL.

 

[Rob Thomas]

Good luck, hope it doesn't turn out to be a huge problem. I hate to see a CTD on the hook.



Later, Rob

 

[Big_Daddy_T]

shucks

Yeah I just ordered some serious goodies to make this thing scream. I had more lined up. I hope the repair bill isnt too much.



Ive beaten everything Ive raced to date but Im not satisfied. More power. Ive had some closed races with hi-po psds so I want to smoke em next time and some of these ricers while im at it.

 

[P Madrid]

You might have another BAD VP44. There are some fault codes that will cut back the lift pump press to less than 3psi, not enough to start and no the vane pump in the VP44 will not pull enough fuel to get it running. When this happens the injection can also be cancel until the fault goes away. Have them overide the lift pump and ck press with Eng not running(12-16psi), idle (10-14psi) and high idle (8-10psi, if lower, volume ck needs to be done for warranty). If the pressures are low thats what took out your VP44. Make sure you get the VP44 with the #5 changes.

 

[fj40charles]

Hey Pablo,



Good to have you on this board. Can you tell us what you mean by "get the VP44 with #5 fix" comment?



Thanks in advance,

Charles

 

[DEZLPWR]

Yes, please elaborate on the #5 fix!

 

[Big_Daddy_T]

lift pump

I have a fuel pressure guage. I hotwired the lift pump and the pressure was about 15 psi. The truck would not start if I hotwired the pump. I had to wait for it to decide to run the pump. Lift pump pressure is good through the whole range. The injection pump is not pumping fuel when it doesnt want to. I cracked the lines during a no start and it would not pump fuel. I wait a bit and she starts right up.

 

[Big_Daddy_T]

I think what madrid said was the fifth revision. Kinda like our lift pumps and all the ones that supercede the previous models.



Cummins tore right into it when it got dropped off. Hopefully I will get it back friday.

 

[P Madrid]

The VP44 has gone through several changes in order to improve its performance. Curently there are five major changes that have been done. I might be able to get a copy of the changes in detail but some were: change of material, eletronic module, extra sealing material on the timing module. I'll get back soon with the info.

 

[Big_Daddy_T]

Cummins diagnosed it as a failing vp44. Second one.