ok i have came along way since my last post but still need help. now my truck runs blows good black smoke, but when you take off down the road it blows white smoke. it still says high fuel rail pressure, its got a miss and when you hit the throttle it hangs where its at for about 2-5 seconds i have read that some trucks do that but mine has never. im thinking my return fuel line might be plugged. from what i have gathered all of my problems could come from that, and since i have replaced the whole fuel system and cleaned out the tank and lines i am running out of options if you can help please help.

 

you have already double checked fuel lines and fittings you sure your not sucking air somewhere and is your pickup tube in your tank still in good shape if you havent checked already look at some of these and good luck

 

I don't think a plugged return will make it white smoke... My dad and I used to make our old dump trucks with big cam Cummins run better by pinching off the return. I'd say air if it's white smoke or lack of fuel in some sort.

 

Questions do not go here...please scroll down and post in the correct forum.

 

Huh???

Plugged return line will generally result in popping the solenoids out of the injectors, not missing and white smoke unless it damaged an injector. Its a possibility.

The hang is normal on a CR, 2 seconds is about right, 5 seconds indicates the possibility of an injector leaking by. A miss and white smoke definitely sounds like an injector misfiring or hanging open. It could possibly be a bad cylinder also.

Soory for your luck but I think you are going to have to do some extensive testing and digging yet.

 

sorry for posting in the wrong spot. lets get that out of the way . im leaning on leaking injectors also but this is the 4th set i have put in in the last 7 months 3 used sets and a new set the new set lasted right at 2 days and none of them would pressure test. so he gave me another old set. if you idel the truck and hit the throttle it blows black smoke, you take off down the road its white, we tore it down to the block to check the cyclinders and they are all fine i live in south east oklahoma and it gets pretty darn cold down here and i am riding a harley, i have been for the last 7 months (when my truck broke down) but back to it. i found out its not the return line. i love my truck and will one day get to drive it again but what i cant figure out is if my injectors are leaking by which i know could cause most of this why do i still have high fuel rail pressue? if you crack a fuel line on the rail the truck runs perfect other then the throttle hanging and fuel getting all over you any help is better then no help thank you.

 

It almost sounds like your rail pressure is way high all the time or maxed out. That would probbaly kill the injectors pretty fast and mess things up.

A rail pressure gauge would help to diagnose that and keep an eye on it later. The FCA is the main culprit in a lot of cases like this. If you haven't yet, swapping it may be worth a shot before going farther.

Having a scan done with the dealer tools will tell you a lot about whats happening and where the source is. Sometimes you just can't get away from taking to the dealer but you can control how much they get into your wallet.