Need help....Fuel/Electronic Problems

gecoveyc

gecoveyc

Diesel Nut
Joined
Jan 25, 2008
Messages
507
Ok I have a 2002 Dodge Ram 2500 2wd 5.9l here at the shop that we just replaced the fuel pump in but cannot get it to start now.

Here's the story and the details:

Truck is a buddy of mines that he took as a trade in. Had it for a couple months sitting on his lot. Started right up every time for test drives and everything no problem. My buddy got tired of it sitting on his lot and decided to just go auction it off. The auction sends a hired hand to pick it up and deliver it to the auction site which is out of town. 5 miles from the auction it apparently just dies and leaves the guy stranded. The auction company has it towed to a shop to have it looked at and offer to pay to fix it since their hired hand was driving it when it messed up. The shop they take it too do some tests or whatever and tell him the fuel pump needs replaced and tell him it will be about $600.

Long story short, he didn't want to put that much money into it since it was a trade in and just needed to get rid of it so he brought it to our shop to work on it himself. He pulled the bed and put a brand new fuel pump in it thinking that would fix it. Goes to start priming it and what not to start it. The truck fires and everything but will not start. So he looks under the hood and fuel is leaking out of the #1,3,4 injector tubes going into the block. (His best guess is the shop the truck was originally towed too loosened them for some sort of test narrowing the options down of what the problem might be) So he tightens them back up and goes back to priming and trying to get the truck to start....no luck

Today we tried replacing the FUEL SYSTEM RELAY but the truck still won't start. It fires and everything just like normal but will not start. I am out of options and basic knowledge fixes and tests and so is he because neither of us are mechanics so I have come to you guys the professionals for help.


Please tell me any and all advice, tests, tricks to try, things to listen for, things to look for whatever it takes to get this thing running so I can get it out of my shop for this guy. No matter how simple or complicated. Thanks guys :thumbsup:

PS: Truck is bone stock
 
You need to loosen all 6 lines and prime until air is out of all lines than try it.
 
Also the only vp trucks ive worked on the lp is on the back of filter canister
 
So basically you're saying they pulled the bed off and replaced the in-tank unit for nothing?
 
Start at the filter housing, loosen a fitting and Make shure you get fuel there. The loosen the feed line on the vp and prime that till you have fuel. Then loosen #1 3 4 5 lines and crank over til they are pushing fuel out. the tighten and it should fire. If not disconect the grid heater and hit with some ether.
 
gecoveyc said:
So basically you're saying they pulled the bed off and replaced the in-tank unit for nothing?
Click to expand...

Im not a vp pro, dont know if they had a retrofit like the early cr or not , but thats how everyone ive worked on is.
Look on the back of the filter canister and see if theres a little black pump.
 
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NEsmoker said:
Start at the filter housing, loosen a fitting and Make shure you get fuel there. The loosen the feed line on the vp and prime that till you have fuel. Then loosen #1 3 4 5 lines and crank over til they are pushing fuel out. the tighten and it should fire. If not disconect the grid heater and hit with some ether.
Click to expand...

^^this

Some of the vp trucks had a retrofit where the fuel pump was mounted in-tank so you may not have wasted your time.
 
Some of the vp trucks had fuel pumps in tank but msot of em were behind the filter canister. If u replaced the assending unit u should be able to tell if the fuel pump was in tank or not.
 
Loosen the supply fitting on the VP, bump the starter to make the pump run for longer than 5 seconds. When you have a good stream of fuel coming from there tighten the banjo back up. Loosen 1, 3 and 4 injector lines and repeat the bump key until you have fuel coming from at least one of those then start cranking on it. The VP will flow fuel to whichever injector is supposed to be firing so you can flow fuel through the pump with out turning the engine over. If you cannot get it to crank after all of this you most likely have other problems.
 
Ok I'm going to start this morning by pulling out the in tank unit and try and figure out if the new one he put in has a built in pump or just the sending unit and then I will start going through the process that ya'll said making sure were getting fuel everywhere and report back to you guys. Thanks for the help so far. I just hope the damm VP44 didn't go out on it
 
You don't have to pull the tank, just do the starter bump and listen for where the pump noise comes from, either the engine bay of the fuel tank.
 
When you bump it the noise comes from under the hood not the tank pump
 
One more thing you may want to check is the return check valve on the VP44. I dunno why but mine quit when I had the fuel system opened up and the truck was a pain to start. You have to loosen the banjo bolt (the one right next to the line coming into the VP44), plug the small hole and try to blow through it. if you can blow through it; it is bad. If not and you start to turn purple from trying to force air through it; it is good. Cleaning it off before doing this is a good idea. I hate the taste of diesel... After that just bleed it as mentioned before and you should be fine.
 
After first initial tests this morning we're not getting any fuel to the filter housing/LP under the hood. Removed the filter and all is dry in there. No fuel. Pump makes noise under the hood after you bump it but no fuel so far. Kinda like it was run out of fuel. Thoughts?
 
Hold a rag over the tank fill nozzle and use compressed air to pressurize the system. Bleed it at the filter with some pressure in the system, then see if the LP will start working.
 
UPDATE****

Ok the unit he replaced in tank is the new integrated lift pump/sending unit. I have another mechanic looking at it with me this morning and he's made some phone calls and I've relayed ya'lls information. What we've come to find is that you cannot buy the under hood lift pump anymore. Instead you have to do the new intake pump and buy a new wiring harness and stuff that bypasses the old under hood lift pump unit. Ya'll probably already knew all of this.

Where can I get this new wiring harness we need to bypass the under hood unit to make this new pump work?

Will the ECM have to be reprogrammed in order to make this new pump work?

How hard is it to install this new wiring harness and bypass the under hood unit?
 
Evrything can be bought at napa. The ecm dosent have to be reprogrammed. Is the original lift pump under the hood bad? I started 2 do this on my cousins truck because the steal lines coming out if his in tank unit rusted off and he got the new unit and it was going to be a b*tch to rewire the new pump so we jus fixed the old unit.
 
Yes the under hood lift pump is bad and apparently you can't buy that particular part anymore. Just the integrated in-tank fuel pump/sending unit we already replaced the stock sending unit with.
 
Didn't have a chance to work on it since I talked to you guys last. Too much stuff going on. Will get the codes off of it today now that our computer is back and let ya'll know exactly what it says. Sorry I haven't gotten them to ya'll yet. Thanks again for all the help everybody
 
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