Chevy and GMC Duramax Diesel Forum banner
  • Hey Everyone! Enter your ride HERE to be a part of this months Ride of the Month Challenge!
1 - 5 of 5 Posts

·
Registered
Joined
·
2 Posts
Discussion Starter · #1 ·
I have a 2002 Chevrolet 2500 with an LB7,
I replaced the injectors and cups, it idles fine, gets up to temp with no issue, even drives ok, until hard acceleration.
After a hard acceleration begins knocking and producing thick black smoke, if I shut it off and restart it it runs fine again.
I performed a cylinder balance test and monitored injector balance rates during the concern, the contribution was equal and roughly matched idle rpm, the balance rates on all 8 cylinders were in the +/- 6-8 range engine warm, but once I shut it off and restart it they go back down to +/- 4.0 range. I don't see any fuel leaks, or notice any fuel in the oil, I replaced the fuel filter and primed the system before even attempting to start it. I purchased the injector super duper kit from Diesel Logic.
 

·
Registered
Joined
·
10,692 Posts
I agree with Brent. Most likely an issue with the injectors that were used. They dont have the greatest reputation. I always reccomend lincold diesel specialties for any injector replacement or upgrades.
 

·
Registered
Joined
·
2 Posts
Discussion Starter · #4 ·
I forgot to mention that prior to the replacement of the injectors the truck had sat and not been ran for 5 months with less than 1/4 tank of fuel.
And again this issue isn't constant or strictly when it is hot or cold, last night I even drove it, 30, 45, 60, and up to 75mph on the highway, the slower speeds were through town and had no issues, the only time I experience the problem is if I hard accelerate then it begins to knock and produce black smoke, as soon as I shut it down and restart it clears up. So with this information would you both still lean toward the possibility of subpar injector quality? Also before the test drive last night I did put fresh fuel in it, I was also recommended to add 2-stroke oil or another lubricity additive, any particular recommendations?
 

·
Premium Member
Joined
·
704 Posts
Search 2SO here before you add any. It contains zinc, which promotes nozzle contamination.

Anecdotal advice saying otherwise is, well, anecdotal.

Use search here to explore your symptoms. While injectors may be the problem, I’m sure you aren’t too keen about going down that road again.
 
1 - 5 of 5 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top