Lift Pump Blues

[JJRSMP]

Well, I'm pretty sure my lift pump is on its last leg. Missing horribly and check engine light on ALL the time. Thought it was originally the PMax wire loose, but no go. My question is , I have been searching the archives about the lift pumps, I do not want another POS which will get me only another 20K on my 1999. Can anyone recommend an aftermarket pump , part#'s, prices, any adapters, This sucks. .

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1999 ISB 5spd 4x5 LB QC, original PMax, 275 Hp injectors.

 

[csutton7]

check out I got the scoop on the lift pump posts it's got plenty of info--it originated with the Holley pump post by me a couple of weeks ago but this one has much more info--chris

 

[Alan Reagan]

JJRSMP, The guys at Southern Truck Parts have tested the latest lift pump from Cummins and says it's the real deal. They put one on an ETC with the capability to require high fuel throughput (if you know what I mean) and if I remember, the pressure didn't fall below 8 pounds at WOT. I understand they are $126 at Cummins.

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2001 HO 6 spd 2500, 4. 10 LSD, Towing Package, Electric Brakes, SPA EGT/Boost Gauges, Fog Lights, Real Backup Lights, Molded Running Boards

 

[Sean Flanagan]

JJRSMP

Check the pump pressure before you replace it. You can hook a piece of hose and a cheap air pressure gauge to the end of the fuel filter drain hose to check it. It could be something else. To be sure, find out what the trouble codes are that are causing the check engine light.

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98. 5 2500 QC LB 4x4 5spd, white. BFG 285x75x16
Cummins 24v w/ TST PowerMAX w/EGT and Boost gauges on A-Pillar. VanAaken CPC. K&N In the factory air box. Stock Injectors, Stock Exhaust (Geno's Muffler Eliminator). Re-routed breather stink tube, 2WD-low kit, SnugTop, JJ Stainless Running boards, Tow Hooks, Bushwacker Street Flares, and a Cup Smoothie.
83,000 miles (1/10/01)

 

[JJRSMP]

Just wanted to let everyone know that I took my truck to a diesel shop which my dealer suggested I do(they pay). The guy checked lift pump, it was ok with the pressures. However, he happened to notice the fault codes were from boost errors, and also I had a "enhancement" box on my truck. He calls Chrysler Star and they want to void my warranty. I call the dealer and tell them about Mag-Moss act, they say they will not pay for further testing and diagnostics. Geesh, I'll just fix it my dam self!

 

[Steve St.Laurent]

When is it missing? Did you completely remove the powermax harness (unplug from the map sensor and the injection pump wire and put the stock elbow back on the turbo and try it? I was having a stumble with my truck a long time ago and I turned off the powermax and it still did it so I thought it couldn't be the powermax. I was wrong, the connection at the MAP sensor wasn't good and I ended up changing harnesses out with TST. The way to test it is to remove it completely and see if it still does it.

-Steve

 

[CCollar-OLD]

Another gotcha in regard to the Powermax is the power lead. The power connection must be firmly tapped to a good power source.

I experienced a pretty drastic miss on my 99, but I, like Steve, assumed that if the Pmax is off it could be ruled out. This is false. For the Pmax to supply a steady voltage to the MAP sensor (steady from the perspective of consistent, not steady from the perspective of steady voltage level), which it does whether or not it is turned ON or OFF, the box itself must have a good source.

Like Steve instructs, reconnect the existing wiring harness into the MAP sensor and disconnect the power from the Pmax (no real need to disconnect the lead to the pump). Drive around for a couple of days to see if the problem occurs.

Hopefully, the truck will run fine. Then make sure you have firmly tapped a good source of power. You may even want to solder the power lead inline with your source. Then check make sure the rest of your connections are firmly in place.

Best of luck

Craig

 

[JJRSMP]

Thanks for the replies. I did entirely remove the powermax and no problem whatsoever. I'll do a more thorough job with connections next time. At least it wasn't the lift pump(yet). Now I have the dubious task of making sure they did not void my warrany!