A buddy of mine has 2005 Ram with a Cummins. He is having issues with no power and dying issues. He replaced the in tank lift pump because we did a fuel pressure test at the inlet of the CP3 pump and we were getting 10 psi at idle but with the motor throttled up it drops to almost nothing. With the new lift pump we are getting the same results. We then tested the pressure before the fuel filter and get the same numbers. When driving the truck it will not pull and will drop speed up any incline and smokes black out the tailpipe. If the truck dies we have to wait about 5 minutes before it will start again. Does anyone have any ideas to what is wrong. He has taken it to a local diesel shop and they had it for two days and found nothing wrong.

 

Has he modded it at all? i.e. any boxes, programmers, etc.

Smoke, no power, have to wait to start it up (heat).......turbo maybe?

 

The truck has no mods, and we have a boost gauge on it now and it will tun up to only 18 psi. I pretty sure that the turbo is fine.

 

How many miles are on this thing? It has a 100K warranty on the engine, he's not over that is he?

 

It does not have very many miles on it at all, but it is a salvage title truck. Don't know if its true or not, but he says is voids the warrnty. Truck was in a minor flood. Yes all fluids have been changed multiple times and has been on the road for months with no problems, until just this week. It started intermittently, but now does it all the time.

 

Yeah, if it's a salvage he's pretty much on his own. Flood damage is a bastard. If he got some nasty flood crud in that puppy, it's gonna get $$$

Where's Drew or jakebrake? They'd be all over this one.

Has the fuel / air filter been changed? Yeah, seems stupid, but maybe it's something simple.

Any weird hissing, like a boost tube is loose or burst? Wastgate stuck open? Hole in the intercooler?

Just by the black smoke, lack of power, and shutting down, it's making me think airflow. If there was no smoke and a lack of power or shutting down, I'd think it was fuel. Have you checked pressure at the fuel rail?

 

what about the fuel filter? could it be getting clogged from whatever is coming out of the tank?

 

All filters have been changed many times, especially the fuel filter. I don't know how you would check pressure at the rail since the CP3 pumps thousands of pressure. The diesel shop that had the truck for two days and found nothing said that they checked the CP3 pump and it was OK. AT WOT it puts out 18 psi of boost, I know that low but its to high for a hump hose to be blown and ther is no crazy sounds. You wouldnt even know the truck had a problem just sitting or reving it up. Just lacks power when driving and under a load. I would say that its some kind of fuel problem and thats causing the low boost numbers, I just don't know what kind of fuel problem it has.

Thanks for the help guys.

 

No body else has any ideas?

 

When you change the fuel filter, did you notice if some power came back for a short while then go away???