Truck turns over, but doesnt start.

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LiftdDodge

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Feb 7, 2012
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Just bought a 99' 24 valve ext cab, long box, auto. Cheap. $2500.

Previous owner says it died on the side of the highway like it ran out of fuel. He checked the tank and it was 3/4 full, decided to replace the lift pump cause it wasnt getting fuel to the injector pump. Then once the lift pump was replaced realized there was no fuel getting to the lift pump. What could this be? the truck just turns over and over and doesnt even try to start.
 
Check fuel flow up to the VP, then check codes. If he replaced the lift pump due to no fuel at the VP you most likely have a dead VP though.

Mumau diesel for the replacement, can't beat their service and they sell Cummins reman pumps, seen to many folks buy from "other" places and have to go through replacing a faulty pump, that was brand new.
 
Loosen the fuel feed line at the injection pump to see if your getting fuel from the lift pump. If not, you have lift pump issues. If you are getting fuel to the injection pump, try bleeding the injector lines. I believe even one will suffice, just loosen the keeper on one and crank it till fuel is coming out. Tighten the line back up and see if it'll fire.
 
LiftdDodge said:
Just bought a 99' 24 valve ext cab, long box, auto. Cheap. $2500.

...Then once the lift pump was replaced realized there was no fuel getting to the lift pump. What could this be? the truck just turns over and over and doesnt even try to start.
Click to expand...

Just FYI, you don't have to run the starter to move fuel from the tank to the injector pump.

Is the lift pump on the driver's side rear of the block or in the fuel tank? Assuming it's on the engine...

You should be able to hear it run by BUMPING the key to the start position and letting the key return to run. The lift pump should operate for around 20 seconds.

If the lift pump operates, loosen the supply line at the injector pump (VP44) from the fuel filter, wrap a rag around it and bump start the lift pump again. It shouldn't take but a few seconds without any back pressure for the lift pump to prime itself from the tank, get fuel through the filter and up to the injector pump. If the lift pump goes through a whole cycle without fuel to the VP44, remove the cap and try again. If still no fuel, you could loosen the line at the fuel filter from the lift pump (tighten - but don't overtighten) the banjo bolt at the VP44 and try bump starting the lift pump again. I don't think this will help unless the fuel filter is plugged solid. If still no fuel, the fuel line is plugged somewhere from inside the tank, through the fitting at the top of the tank, through the rubber line to steel line along the driver's side frame and finally through the rubber line to the lift pump.

If you get fuel at the VP44, you'll need to tighten the supply banjo bolt and loosen as many fuel lines as you can get at the head. #1 is good, but you'll need to remove either the 8mm clamp bolt or the 10mm plenum cover bolt also to allow the line to move from the head a little. I usually opt for the plenum bolt. It just seems easier. Forget the one right behind the air horn, and grid heater - it's a PITA. You should be able to get most of them loosened. #6 required removing the lift eye with a 15mm socket 1/2" drive. Put it back when you're done. It takes just a minute and it'll always be there - especially when needed (pet peeve).

Then, crank the engine for 20 to 30 seconds at a time and give the starter 10 minutes to cool down. You should get fuel dripping from some of the high pressure lines. Put a rag or two down under the fittings so fuel won't run down toward the back and make you think injectors are dripping fuel that really aren't. You can also run your finger around the fitting at the head to see if it's wet. As they start dripping, you can tighten them. Eventually, it'll start....If you don't get any fuel from the high pressure lines....The VP44 probably needs attention.
 
One thing to add to ol blue's post, once you have fuel at the VP inlet and have cracked injector lines #1, 4 and 5, continue bumping the starter and running the lift pump, you should get fuel dribbling from at least one line this way. Once you have that, then start cranking. It normally takes about 3 starter bumps to get fuel out of the injector lines.
 
Thanks for all the help guys! Im a powerstroke guy turned Cummins after many POS Fords that Ive owned so wrenching on a Cummins is new to me. I found a VP44 off of a friends truck that he converted to a 12v injector pump so he is gonna let me steal it off him for $75. hoping that will do the trick then once the truck is running im gonna be looking at you guys for help to get me into the 600-700HP range.

Thank you.
 
If you wanna get to that HP range you might as well throw that VP in the trash and go straight to a P-Pump conversion.
 
They have all mentioned the BEST way to get it to crank, however if you find that you have fuel through the VP but still cant get it start give her a little snort of ether. Dont drown it which Im sure you know. I replaced a lift pump on a truck awhile back that I was sure the VP was dead as well cause it had done the same thing you have described. I couldn't get fuel through the VP after the pump install gave a few whiffs of the juice and truck has ran fine ever since.
 
I have never heard of a P-Pump conversion?

She took a litte drink of ether, still a no start and im baffled. injector pump it is!
 
P-Pump conversion - Oh, this is a slippery slope you're heading toward!

You gave it a squirt of ether and it didn't even try?

It might not be a fuel problem then. There are anti-theft "deterrents" in the PCM and ECM so a mismatch won't let the electronics operate. It'll just crank forever - until the batteries are done and/or the start burns up anyway. HOWEVER, a direct shot should still get it to pop, bang, and stumble around a little.
 
If the tach doesn't read rpm while you are cranking, could be a cam position sensor, but that should throw a code. I'd say you didn't use enough ether to get combustion. I would use it as a last resort.
 
I have a complete, running 96 12 valve.. a p pump conversion is taking the pump off the 12 vavle and putting it onto my 24 valve?

When I was spraying it with ether, the truck would turn over.. then turn over very fast as if it wanted to started but never got that far. Going to try to borrow a buddys code reader tomorrow and see what codes it throws up. the guy I bought this truck off of swears its the injector pump.. but then again he also thought it was the lift pump so he went and replaced that aswell.
 
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