I thin my '04.5 has a dead lift pump. I'll check it out this weekend. Is this covered under warranty? Should I go aftermarket anyway? Will it damage my CP3 if I can't get to it right away?

 

A dead lift pump cannot damage the CP3 - the CP3 has an internal lift pump that will draw fuel thru the lift pump and filter - if not enuff fuel to satisfy the internal lubrication requirements, the CP3 simply will not pump injection pressures, engine dies.

To test, pull the lift pump plug and observe operation for ~5minutes - if the engine dies, the CP3 cannot draw fuel thru the stopped lift pump and filter.

If the engine runs, you'll need to pressure test the lift pump to see if it will pump thru the filter element -
- kill the engine
- switch the key on-off-on, the lift pump should run 25 seconds in the prime mode
- if the pump does not run, it is failed
- if it runs, crack the banjo bolt on the pipe that runs from the filter output to the CP3, fuel should squirt out at lift pump pressure = if not, the pump is failed or the filter is plugged
- then test it at the yellow-handled water drain - the drain is pre-filter - if good pressure there, the lift pump is good, but the filter is plugged

Early '03-'04 CP3 had some internal leakage problems, not caused by any lift pump problems - if the engine dies when the lift pump is dead and won't restart, in some cases DCX has upgraded the lift pump to the in-tank version when they replace the defective injection pump under warranty .

 

where exactly is the lift pump plug? I think i may be having problems with my lift pump and need to test, but i'm not really familiar with the engine yet

thanks

 

If the original pump is still on the fuel filter housing, the power plug will be on the motor - side of the engine facing the brake booster.

 

I have an early '04 3500. My lift pump went bad and I called the dealer. They no longer replace the lift pumps with the one on the back of the filter assembly, instead they retrofit your truck with the in-tank setup. If your truck is still under warranty then that is what they would do. I junked the factory parts and went with a Walbro 392 external pump that I put along the frame rail. Works great and keeps my pressures up! In the kit they will give you a plate that goes in place of your factory lift pump, and the Walbro 392 will be bolted to the framerail. It is fairly easy to install, just do it with an empty tank so that you don't get diesel fuel everywhere! If you don't want to go with Walbro, you also check out FASS, they make a good product also. You may be able to go to their website and download some instructions and get an idea of what you are getting into.

 

what is a ballpark price for this setup? Am I better doing this than getting the in-tank setup?