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Hard start, smoke, rattle, no power, mpg drop - no codes

542 Views 12 Replies 3 Participants Last post by  10sc
So a few days ago a neighbor replaced my valve and rocker gaskets to stop an oil leak. While he was in there, I had him put in new wire harnesses to the injectors. The next day and I'm smokin all the time and the normal diesel "rattle" is a higher pitch than what I'm used to. A small increase in the pedal and I'm blocking out the highway with black smoke. If I get on it to pass a semi or something large, my engine will not throttle back until at least a 1/4 mile after I let off. The harder I hit the pedal, the longer it takes to throttle down.

Reading all the posts on here, I figure I've possibly got an air problem. Now I didn't read all posts but the last part about my truck not throttling down is something I didn't find which is why I'm creating yet another post.

I've seen all the posts about checking the intercooler boots and possible injector issues but it seems to me a mighty odd coincidence that this happened right after changing out a couple of gaskets and wire harnesses. Is it possible that a wire harness is defective?
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Sounds very much like overfueling injectors issue, or else he put a big tune on it when he did the work.
I would advise parking it till u find the issue, running it hard with injectors overfueling is a good recipe to wipe out rings and pistons.
I'm guessing blew injectors somehow, do u have your rail PRV blocked?

Also check wiring to rail pressure sensor, possibly a poor connection that made rail pressure go way to high.

Honestly seems like we're not getting the whole story or something, just seems strange that changing rocker seal makes this happen.
Ouch! Pulling out the bad injectors, he noticed a valve sticking. Investigation on why finds a melted piston and scored/hole cylinder. Sooooo. . . my engine is toast without a full rebuild. Money is a problem. I wonder what kind of trouble I'd get into if I tried to put a 1996 cummins in my truck. I can get one for $3500.
Don't do that. 🤣
No honestly it's your decision, I'm not your boss or financial advisor.
If you can do the work yourself it's really not that terribly expensive.
Do u have any mechanical skill? Do u have any friends that could help you?
I'm not surprised you have melted pistons that's not uncommon running with bad injectors.

Anyway I'm putting mine back together, hoping to put the head on tomorrow, here's my thread on it.
I might get slapped for this but IMO the CR engines are a definite upgrade from a 12v, yes they are more picky and complicated but the ripping power and torque out of these things is amazing.
Here comes the financial advice. If u have another vehicle run it to work and start saving as much as possible and start researching parts.

If you don't have another vehicle go spend the 3500 on a little gasser that will get u to work.

Do u have the new set of injectors already? The engine rebuild shouldn't be any more than 7k if you can do it yourself and bum a little help from a friend now and then.

Ok I'll shut up now.🤫🤫🫢🫢
Man I wish u were my neighbor.
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