Noob to the duramax

[GreasemonkeyHD]

I've only owned 1st gen cummins trucks and a 1st gen powerstroke ( that I am still currently driving). Sold my beloved first gen dually and picked up an 04 ccsb 2500hd with the lly duramax. The previous owner swapped a cab off of an lb7 truck after a tree fell on it. All was good then he started having a problem with the truck smoking raw diesel smoke and misfiring. He talked to 3 different diesel mechanics, 2 of them said the injectors were bad and 1 said the ficm was bad. He gave up and sold the truck. Since I've got it. I started with checking the section of the harness that runs behind the alternator and found no broken wires. The check engine light wasn't on and it smoked heavy and misfire one one cylinder steadily. Tried a half bottle of hot shots and after a minute or so the smoke cleared. The motor ran pretty smoothly. Took it for a short drive (about a mile or so) and it smoked very little. About the time I turned around it started clattering and sounded like an old tractor, check engine light came on. Putted it back to the house and it idled rough in the driveway with no smoke. Showed a p201 code for injector control circuit 1. Shut the truck off , let it sit for a few minutes. Fired it back up and it was back to running smoothly with no smoke, gave it a couple revs and back to the old tractor balance rates pictured are right after the run

 

[GreasemonkeyHD]

Didn't want to post a paragraph but I wanted to tell as many details as I could. Since this run its thrown different injector control circuit codes every time. Just one though never multiple codes at a time. It also started smoking again and misfiring. Starts right up and has no blowby

 

[Ron Nielson]

See here: https://www.dtcdecode.com/Chevrolet/P0201

Looks like there is a faulty connection to the injector for cyl #1. Try unplugging and then re-glugging the connector, use some DeOxit if you have that, or tuner cleaner, or electrical contact cleaner, etc.

 

[TheBac]

Moved to LLY section. Good luck.

 

[GreasemonkeyHD]

Moved to LLY section. Good luck.

Thank you and sorry I posted it in the wrong place

 

[TheBac]

No worries.

 

[GreasemonkeyHD]

Went through and ice picked all injector plugs besides #6 and #5 I think. It's still early lol. Once warmed up it will miss intermittently on 1 cylinder with a very light haze. Then kick an injector control circuit code on 1. If you Rev it lightly you can hear an injector knock and then it will go into tractor mode. Sometimes it will just do it on its own

 

[GreasemonkeyHD]

Anyone have another ficm I could try?

 

[Chevy1925]

Sounds electrical. "tractor mode" is the FICM shutting down one bank of injectors as one injector is looking connection. this creates an open and the whole bank of injectors goes down.

being that injector 1 keeps coming up and then causing the trip of the codes/bank shut down, id start looking at the wiring there, ohm the injector solenoid or even move it to the opposite bank and see if the issue switches sides. if it doesnt, the wires or connector to the injector may be bad regardless of ice picking them. Genereally is injector 2 and 7 that are the culprits but may not be in this case.

just fyi, FICM are not cheap anymore and a couple members have been burned on "loaners". unless you have someone local, i wouldnt expect someone shipping you one to test with

 

[GreasemonkeyHD]

sometimes the icepick trick doesnt do the job and you have to install new plugs on the injector harness. cut the old ones off and splice new ones on. everything you're mentioning sounds like a harness issue

Well I took an extra good look at the truck today. Looks like #8 injector has been replaced along with the plug, plus there is a weird almost home made bracket or something under it kinda hard to see in the photo. It's thrown a code for 8 a time or two. Also #4 has weird black sludge around the line nut that indicates leakage although I don't see any fuel leak while it's running. The truck will have a dead miss and smoke like a chimney while it's cold, once it gets kinda warm it will smooth out and the smoke will clear then all of the sudden either 1, 6 , or 8 injector control circuit code and run like a tractor. The pigtail for #1 appears to also have been replaced.

 

[PureHybrid]

I'd say the black sludge on that line is from gunk dripping from the EGR valve above it. Second picture with the bracket looks like the "fix" for the harness that you can buy. Possibly pull back the wiring loom and check out the previous mechanics splicing job.

 

[GreasemonkeyHD]

Just so we're clear I was talking about the bare piece of flat steel under the black painted bracket. I wish I could've gotten a better picture of it

 

[GreasemonkeyHD]

It also appears that the black gooey injector line has rubbed throught the plastic split loom on the harness

 

[PureHybrid]

I can't tell what the other bare metal bracket is bolted to

 

[GreasemonkeyHD]

I can't tell what the other bare metal bracket is bolted to

It has the 2 outside bolts going into the valve cover and the center bolt is going into the body of the injector. It's on #7 the passenger side rear injector

 

[PureHybrid]

It has the 2 outside bolts going into the valve cover and the center bolt is going into the body of the injector. It's on #7 the passenger side rear injector

Is the injector hold down still there?

 

[GreasemonkeyHD]

Is the injector hold down still there?

I guess I'd have to look at an easier to see injector I'm not sure what one looks like lol like I said I'm a noob to the duramax

 

[08lmm72mm]

The piece that says pdm on it is the injector hold down.

 

[GreasemonkeyHD]

The piece that says pdm on it is the injector hold down.
View attachment 106220

I'm starting to think that piece is a homemade injector hold down because where the center bolt threads into the injector body there is a nut that looks like it holds down the injector

 

[08lmm72mm]

Could be, I'd take it off and pull that Injector out to see. If there isn't a hold down bolt in there where it should be I bet the hole stripped or the bolt is broke off. Pull that injector and see what is going on in there, pickup a new copper crush gasket and o ring.