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slr2000

99 low pressure fuel pump not working

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I have a 99 5.9 with a low pressure fuel pump not working. I changed out the pump today (160 bucks)with a new one but still no work. I ran out of time today to check voltage on the pump but I think it is a shoe in that it is not getting voltage during crank. I tried the bump engine but don't start, to hopefully get the low press pump to initiate but it will not. I did get the pump to work once a couple months ago and I think it happened when I drained the fuel filter through the bleed valve on the filter. Then went back to crank and the pump initiated. When I swapped out the pump today the filter was drained but it still did not initiate. All of that leading me to believe that it was a random initiate that once that it did work as it is supposed to.I can either mist the turbo and the truck will start up and run great.I know not to make this a habit or stand near when I start. Basically mist trubo, replace filter, go to cab start.I also just finished (this week) a 1500 lock n stitch repair on a 17 inch crack in the block.So, now I'm trying to keep monies spent at a low amount. Just from a day of working on this problem I can already see 3 things I could buy that would cost a grand that I don't have. Code reader, fuel pressure meter, fass fuel pump, dealer repair manual.If I could get some help here in working out this issue I'd appreciate it.The truck is still a pretty nice truck so I'd like to get a secure fix on it even if it is a solid work around.I have already read on this forum such things as possible air leaking in, possible bad diaphram in injection pump with others issues on the low pump not chiming in.My questions are:1. Is the low pump working to keep the engine running when I have it running? Or can the engine run at full pressure with out that pump once started? This could tell me that the pump is working but there is a prob with the pump on start up.2. If I find no voltage then where do I go from there. What fuses do I check? I checked the relays titled fuel.3. What pins do I short to read out the codes on the dash and where can I find the codes for this engine? There are codes stored but I'm trying to keep from buying a code reader for the fact that money is tight and I don't know what I'll need to buy next.4, Would there be an issue with Wiring a new wire to the low pump that would initiate when the truck is switched on? Sounds like a jury rig I know, but it is just a matter of getting the juice to components in my thoughts.

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I don't know which year they started to do this but you can get some codes in the odometer window by turning the key to on (not start) back to off 3 times... stop with it "on". Any codes will flash in that window. The LP (Lift Pump) should run for a second to pressurize the lines when the key is turned on. The LP must keep a minimum of 10 psi to the IP (Injector Pump) when running. The IP is Fuel lubricatated... Not enough fuel pressure often precipitates failure of the VP44 IP. DO NOT try to start if you don't have fuel to the IP. I hope it's not too late already.It would be a help if you described your truck in the signature space in the user control panel section. Russ

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Little insight... The VP44 has the ability to run without a lift pump but does serious damage to itsself when the fuel pressure drops below 10 PSI... Lift pump test and pressure requirements... http://mopar.mopar1973man.com/cummins/2ndgen24v/lift-pump-diag/lift-pump-diag.htm Then how to pull error codes... http://mopar.mopar1973man.com/cummins/2ndgen24v/obd2-error-codes/obd2-error-codes.htm

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This is a really great site, thanks for all the hard work.Do you have any suggestions where I can get a reasonably priced pressure gauge?Also, what must be the abs block started running non stop today. I had to disconnect it.Facing the front of the truck it is the block in the far right hand corner that is connected to the brake lines.Any common causes of this known to you?

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slr,I found my mechanical gauge on Ebay. I just mounted it in the truck. It's the first one every VP44 24V'er should have.Welcome to Mopar1973Man.com Best of the best, as far as I'm concerned! :thumbsup Dave

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