Need some Help on This!

[jman]

Truck has been low on power and setting a P0251 code for a while. The other day it died on me several times when I would roll to a stop. Had to crank it for about 10 seconds to get it to restart. Got it going, but no power. Took it to my diesel mechanic and he put the scanner on it and drove it. Did the tests related to 251 code and everything checked out. Had me take it to Dodge to see if their scanner would find an underlying problem. They did return flow test and it was was over spec. I think 800mL. Tightens connector tubes and now at 600mL,but still out of spec. Injectors were rebuilt at 113K and now I'm at 132K. Any ideas? This thing has me beat down. When it idles it tries to die, but catches itself at the last minute. Idle sticking at 1000 rpm and tech says when it does this the rail pressure is 7K and should be around 5K. FCA has been replaced w/no change. I need help bad. Been in the shop for a week and I've gotten nowhere, but poorer. Thinking ECM for the 251 code, but what is causing the excess return flow.



Sorry so long, just trying to give all the details.

 

[rbattelle]

Have you replaced the rail pressure relief valve?

What about the lift pump?

Ryan

 

[sag2]

Are you sure they checked the return flow correctly? This is way to high for injector return, and is on the high side for pump return. Pump return is less than 1000ml at idle in one minute. Injector is less than 180ml in one minute. It sounds like your shop is not using the 9012 to separate the pump from the injector return. A more normal return for a truck with some miles is 400-600 from the pump, and 70-140 from the injectors.

What did the P0251 checks find? Did everything check out OK as far as the FCA and wiring?

 

[MMeier]

I'd be leaning toward a faulty pressure relief valve.

 

[jman]

Took it out of the dealer because they weren't getting anywhere. Took it back to my diesel guy and his return flow test was 100mL or close. (Can't remember exactly) Wiring checks out, FCA Ohms out within spec. Idle is sticking at 1000 rpm occasionally and when it does this the rail pressure is at 7K when it should be in the 4-5K range. FCA never helped this at all. Driving us all crazy at this point. I have a FASS and it is doing its job. He wants to try a CP3, but the way this thing is acting I'm not too confident in that right now. I will pass on any ideas any of you may have. I'm driving our chevy Trailblazer right now. That ain't cool!!!!!!