2007 duramax problem ? ? ?

[sweetk30]

2007 duramax in a 5500 c&c truck with allison auto .

keeps tossing a p0204 but some times a p0201 for injector problems.

its had the 2 common injector pigtail plugs replaced and also the #4 . crimped / soldered / heat shrunk .

also the #4 injector has been replaced with a reputable reman unit from good long time standing company .

it pings like a gas engine with cheep gas and bad timming settings .

only does it when it wants to . but more when air temp cold or huge drop in temp outside. and likes to do it more in the 2200-2700 rpm range along with highway speed of 65-73 mphish . but has been doing it more at lower speeds now and then . some times just rocking the truck when running in park can make it do it .

this can go 1 min from clearing code to weeks with no problems . its all over the board .

same fuel from same tank at shop every fill up . other trucks in fleet no problems . fuel filter in truck changed every other oil change most of the time.

thing kickes the 2 codes most of the time and goes and cuts off the high voltage to injectors and reduces power on engine till cleared .

short of tearing all the loom and tape off and checking every inch of wiring on the engine what is the problem ? ? ? any ideas help !

 

[Russell]

Have you tried disconnecting and reconnecting the two big engine harness connectors on the driver's side valve cover? I had an 07 come through my garage with similar symptoms which were immediately and permanently repaired by doing just that on the advice of a fellow CK5er

 

[sweetk30]

have to check .

I did some digging on internet last night . found a tech bulleten from gm some one posted on these in the med duty trucks . the high volt box is pass side off bracket to right of alt . they say check the wiring it can rub on the alt bracket and cause this .

 

[doubletrouble]

I had a similar problem on my 04 duramax, where the main wires go over the valve cover on the driver side one of the wires had a very small spot that wore threw and was shorting out. I found it at night working on it outside with a flash light, the light reflected off the copper wire. I had looked at it in the daylight and never noticed it.

 

[sweetk30]

I have temporally fixed it ( don't wana say fixed and jinks my self )

5 zip tie's and 6-8" long section of old radiator hose .

that tsb I found about check behind alt bracket on med duty dmax engines was spot on .

the protector layer was worn threw and almost ready to strip wires . didn't find any worn threw . so just added hung of hose and secured it with zip tie's and sofar over a week now zero pings . . . . .

so to say again ( knock on wood/truck/vehicle ) its temporally fixed . . .