6.7 cummins low on power

[Melendez2500]

2017 ram 2500 6.7 cummins. 79k miles. Truck is fully deleted (EGR/DPF/exhaust). Adult driven. Problem started very suddenly. Truck has never had any issues I've owned it and maintained it since brand new. No check engine light or codes, no exhaust smoke at all (usually dumps some black smoke upon heavy acceleration and my tune), no rough start or idle, exhaust brake is working as it should, fuel rail pressure is meeting demand (idle around 4600 PSI / WOT is getting about 20,000 PSI). From my research it should be getting some more fuel pressure at WOT. Boost is only reaching 21 PSI at WOT which is lower than normal for the truck also. Truck has no power very very sluggish. Low speeds feels ok..if you don't get on it and will get to highway speeds... eventually. Made sure all Intercooler boots and the whole intake/turbo system is sealed well and not having a major boost leak. S&B intake Air filter is clean, MAF sensor looks to be clean and good. Both mopar fuel filters recently changed have 675 miles/45 gallons through them. I ordered a new fuel rail pressure relief valve to see if that solves anything. Also have a boost leak kit on the way to attach at the turbo and pressurize the system to make sure I didn't miss any possible leaks. It seems to me like a fuel or boost issue but everything I have tried so far has had no improvement. Any other ideas?

 

[06 Dodge]

2017 ram 2500 6.7 cummins. 79k miles. Truck is fully deleted (EGR/DPF/exhaust). Adult driven. Problem started very suddenly. Truck has never had any issues I've owned it and maintained it since brand new. No check engine light or codes, no exhaust smoke at all (usually dumps some black smoke upon heavy acceleration and my tune), no rough start or idle, exhaust brake is working as it should, fuel rail pressure is meeting demand (idle around 4600 PSI / WOT is getting about 20,000 PSI). From my research it should be getting some more fuel pressure at WOT. Boost is only reaching 21 PSI at WOT which is lower than normal for the truck also. Truck has no power very very sluggish. Low speeds feels ok..if you don't get on it and will get to highway speeds... eventually. Made sure all Intercooler boots and the whole intake/turbo system is sealed well and not having a major boost leak. S&B intake Air filter is clean, MAF sensor looks to be clean and good. Both mopar fuel filters recently changed have 675 miles/45 gallons through them. I ordered a new fuel rail pressure relief valve to see if that solves anything. Also have a boost leak kit on the way to attach at the turbo and pressurize the system to make sure I didn't miss any possible leaks. It seems to me like a fuel or boost issue but everything I have tried so far has had no improvement. Any other ideas?

Have you tested the MAF to be sure its good? If not it would be a good idea to do so...

 

[crash68]

fuel rail pressure is meeting demand (idle around 4600 PSI / WOT is getting about 20,000 PSI). From my research it should be getting some more fuel pressure at WOT. Boost is only reaching 21 PSI at WOT which is lower than normal for the truck also.

Are those pressures under load or just pushing the pedal to the floor? It usually takes putting a decent load on the engine before peak boost and fuel pressures are achieved

 

[smiley]

Did it start after you changed anything like the oil, the fuel filters, bought fuel, etc?

Have you ever used some fuel injector cleaner? Mine doesn’t really do a crazy amount of boost but it would depend on tune you are running too. Are you comparing someone else with that tune or just yours against stock? Checked wheel bearings and axle bearings? Brake calipers sticking? Just some ideas.

 

[Dennis Shellito]

Make sure it isn't loosing boost through the grid heater gasket on the drivers side of the engine. No CEL or codes popping up? If the fuel control actuator on the fuel fails, you can unplug it from the harness and see how it runs. It might throw a CEL, but it will tell you if that is indeed the problem.