Engine/Transmission (1998.5 - 2002) 2001 Fuel Lift Pump won't run the 25 Seconds on Engine bump.

[randall53]

Hello all. As usual, I found this awesome place while searching for an answer to a problem. Lot's of great knowledge on here I can see. Maybe someone can help me with my Fuel Lift Pump. I changed my fuel filter per the manual, as I have before, and everything went smooth....BUT, When I started it, it ran for maybe 5 seconds and died. It won't start now so I figured air in the system and that I just needed to bleed it. The problem is, the fuel lift pump will only run for about 2 or 3 seconds as it does when turning on the switch, but it does it even after bumping the engine. If it would run the 25 seconds as the manual states, I'd have been through in 15 minutes. So, does anyone have any ideas whey the engine bump process won't run the FLP for the 25 seconds? Any help would be greatly appreciated.

thanks!!

Randall

 

[VolsFan]

Are you running the stock carter lift pump in the stock location? Do you have a fuel pressure gauge installed? The carters will fail without warning. Good luck!

 

[randall53]

Yes VolsFan. It is the original installed right behind the filter next to the engine block. It has no fuel pressure gauge. I bought the truck new and it now has 140K on it. It began missing this morning while towing a 4 wheeler up a mountain. I changed out the fuel filter and it really needed it, but now it won't start. I can hear the pump run normally, 2 or 3 seconds when I turn on the key and I see no leaks. I was figuring maybe the fuel system needed bleeding because maybe air between the filter and the injector pump, but now I'm not sure. I may call a dealer tomorrow and see if I can get another one. The truck is completely stock.

 

[VolsFan]

If the dealer even stocks the lift pump you'll likely pay dearly for it. You are definitely in the minority of folks that have had that long of a run with it. Is it the original I take it as well as your VP-44 (injection pump)?. Speaking from personal experience when my old truck started developing a miss it was the injection pump. It was under a year warranty and I was in the last week of the warranty period. The shop put in a new one no charge. Hopefully you get off easy. I would strongly consider the FASS DDRP, Genos garage sells them. It will mount in the factory location DDRP- dodge direct replacement pump

 

[VolsFan]

http://www.genosgarage.com/category/fass-fuel-system

 

[SnoKing]

Relocate it to the frame while you are missing around with the new pump and install a fuel pressure gauge. SNOKING

http://www.genosgarage.com/product/vulcanrelokit/fuel-system-accessories-replacement-parts

or

http://www.genosgarage.com/product/vulcan-vpps9802-kit/fuel-system-accessories-replacement-parts

 

[Bob4x4]

When you tried starting the truck with out priming the system and it died you now have air between the vp and the injectors.Even with a known good lift pump you will need to crack lines open to bleed the air.To test your lift pump pull the supply hose to the vp and bump it.Note the key must be turned off between bumps for it to cycle properly

 

[randall53]

If the dealer even stocks the lift pump you'll likely pay dearly for it. You are definitely in the minority of folks that have had that long of a run with it. Is it the original I take it as well as your VP-44 (injection pump)?. Speaking from personal experience when my old truck started developing a miss it was the injection pump. It was under a year warranty and I was in the last week of the warranty period. The shop put in a new one no charge. Hopefully you get off easy. I would strongly consider the FASS DDRP, Genos garage sells them. It will mount in the factory location DDRP- dodge direct replacement pump

Thanks VolsFan. Yes it was a miss while under load and yes it is the original FLP. The fuel filter was very nasty which is my fault for not changing it sooner, which led me to believe that could have been the problem. After I replaced the filter, it started right up and ran for about 5 seconds and died. It hasn't started since. The puzzle I have is why the FLP won't run for the 25 seconds when the engine is bumped, but will run for about 3 seconds as it still does when the switch is turned on. This means I can't prime anything. I did cycle the pump 5 or 6 times hoping it would start, but it did not. I'm really hoping this doesn't mean the ECM isn't sending the 25 second run signal to the pump. I'm going to get a fuel injection pressure gauge today and see if the pump is doing anything at all during the 3 second run, but I'm betting it's not pumping fuel even though it's running for the startup routine. I guess I'll know more later today.

Relocate it to the frame while you are missing around with the new pump and install a fuel pressure gauge. SNOKING

http://www.genosgarage.com/product/vulcan-vpps9802-kit/fuel-system-accessories-replacement-parts

Thanks Snoking for the suggestions. I am looking into both of those ideas today. Where is the best place to install gauge? Immediately after the FLP?

 

[NIsaacs]

I am sure your lift pump is bad. After you bump the starter jump out and smack the pump with a plastic screwdriver handle and see if it starts. Install the gauge after the filter, usually right at the vp inlet. You can get an oem pump at most auto parts stores.

Nick

 

[randall53]

I am sure your lift pump is bad. After you bump the starter jump out and smack the pump with a plastic screwdriver handle and see if it starts. Install the gauge after the filter, usually right at the vp inlet. You can get an oem pump at most auto parts stores.

Nick

Thanks for the help NIsaacs. The problem I'm having is not that the LP won't start, but rather it will only run for 2 or 3 seconds whether I simply turn the ignition on, in which this condition is normal, or if I start over with it by letting the startup systems stop and then bump the starter. When I do the starter bump, the pump will start, but will still shut off after the 2 or 3 seconds as it does in the first instance. I only get a 2 second run instead of the 25 second run out of the LP after bumping the starter. I've tried the starter bump both ways, letting the code sequence clear first and going straight to the starter bump but I still only get a 2 second LP run time. This is what really has me puzzled. If I could get the 25 seconds run, I could try to prime the system but that's hopeless with only 2 seconds of LP running. It's like either way, the ECM is only sending a run signal for short duration and not the 25 second run. I'm not sure which way to go.

Edit comment: From all the info I'm seeing, the stock LP is toast. 140K and 15 years is a very abnormal run for the stock LP pump. I'm feeling the need to replace it whether it's good or bad. It's time. I'm going to move the pump to the frame also and add a pressure gauge which seems like a very good idea and doesn't add much cost. After that, maybe I'll be able to figure out which way to go.

Thanks to everyone for the help!! If anyone has any suggestions or ideas please keep the coming! I'll probably not start this project until Wednesday anyway since I'm researching LP's on the internet and locally. I'm not really interested in performance pumps since the stock one always did whatever I needed in towing which was a fifth wheel RV or small boat and I need to be conservative with costs.

 

[NIsaacs]

I think the signal is there, the pump is bad. Did you whack on it? They can act like that if the motor is bad.

Nick

 

[randall53]

I think the signal is there, the pump is bad. Did you whack on it? They can act like that if the motor is bad.

Nick

Not yet, but I'm going out to do some more checking and I'll definitely give that a try. I agree though. The pump is probably toast. Thanks. I'll post any develpments in this problem and any fixes. Researching these posts are a great way to help others.

 

[randall53]

When you tried starting the truck with out priming the system and it died you now have air between the vp and the injectors.Even with a known good lift pump you will need to crack lines open to bleed the air.To test your lift pump pull the supply hose to the vp and bump it.Note the key must be turned off between bumps for it to cycle properly

I think I'll start right here. Good info Bob4x4! Thanks!

 

[JR]

I think I'll start right here. Good info Bob4x4! Thanks!

Yes, need to prime the system for sure, after you get the lift pump issue resolved and have steady fuel to the injection pump. Depending on how much you've cranked the engine with no fuel between the LP and injection pump you may have to crack several of the lines. All above suggestions on lift pump location and fuel pressure gauge are almost mandatory for the VP trucks. Carter might be interested in your original pump, that's probably a record!

 

[randall53]

Thanks JR. I've definitely been lucky with the LP, now if I can just decide on a replacement from all the ones out there. I'm just hoping the VP has survived. Money is really tight right now. I understand these things are very expensive.

 

[NIsaacs]

On a stock truck I would use the stock lift pump in the stock location. If it quits on the road they are easy to find and only take about 30 minutes to change. If you relocate it you will need a wire harness extension and will need to cut your oem fuel line and adapt it to the pump. Did you check for codes?

Nick

 

[SnoKing]

On a stock truck I would use the stock lift pump in the stock location. If it quits on the road they are easy to find and only take about 30 minutes to change. If you relocate it you will need a wire harness extension and will need to cut your oem fuel line and adapt it to the pump. Did you check for codes?

Nick

Changing a stock pump relocated to the frame is actually easier that changing on one the side of the block in the OEM location. Ask me how I know???? Took about 10 minutes. SNOKING

 

[NIsaacs]

Changing a stock pump relocated to the frame is actually easier that changing on one the side of the block in the OEM location. Ask me how I know???? Took about 10 minutes. SNOKING

Yes, but the first one is not

Nick

 

[mwilson]

Sounds like a bum lift pump to me. The question is has it harmed the VP-44.

So I would recommend the Cummins replacement OEM pump. You don't need any more than that on a stock truck. I do recommend at the least a warning light kit if you don't want to install a gauge. Regardless you must monitor the lift pump, they fail without warning or symptoms. Have caught two dead ones over the years just while doing a filter change as you now are.

So the light kit.....http://www.xtremediesel.com/BD-Power-1081130-Low-Fuel-Pressure-Alarm-Light.aspx

Cummins redesigned the pumps some years back to allow fuel to pass through in the event of a pump failure. Less stress on the VP-44. I can't help but wonder if the aftermarket chain store pumps would have that feature.

This is the bulletin from Cummins announcing the change....

 

[mwilson]

Now the 4932707 pump mentioned above has changed again to a 4943048. This should sell for about $220.00 at a Cummins facility.

There are some engines that require a short jumper harness for the updated pump, that would be Part Number 4025182. That should sell for $25.00 or so.

Now there were also some kits back along that had the updated pump and harness all in one box under one part number....3990082. That should sell for about $212.00. Then you get the pump AND the harness for less than the 4943048 alone. Just a thought. There is one 3990082 sitting in the Harrisburg warehouse, I just checked.