Chevy and GMC Duramax Diesel Forum banner

LLY Injector Miss w/ Balance Rates

3K views 11 replies 4 participants last post by  mray 
#1 ·
Greetings All, I have a 2005 LLY that I recently purchased and got running, although poorly, it is running. I have an issue that I need help with. I pulled the Balance Rates using my OTC Genysis Evo and it is as follows:
Cyl 1 -1.9
Cyl 2 -1.9
Cyl 3 15.0
Cyl 4 -1.9
Cyl 5 6.0
Cyl 6 15.0
Cyl 7 -1.9
Cyl 8 -1.9
Actual Fuel Rail Pressure 6334.1 psi
Desired FRP 6235.0

I took that data and swapped out some used injectors to see if I could isolate the problem and the balance rates are

Cyl 1 -1.6
Cyl 2 -1.6
Cyl 3 15.0
Cyl 4 5.5
Cyl 5 15.0
Cyl 6 15.0
Cyl 7 -1.6
Cyl 8 -1.6
Actual Fuel Rail Pressure 6465.

Any input would be greatly appreciated.
 
See less See more
#2 ·
I also forgot to mention that I have codes PO300C Engine Missfire Detected, Code PO303C Cylinder 3 misfire detected, PO305C Cylinder 5 misfire detected, PO306C Cylinder 6 misfire detected, P1229C Injector 3 Output circuit, and P1238C Injector 6 output circuit as well as P2227C Barometric Sensor Performance. Any Ideas,
 
#3 ·
Have you tried running a concentrated dose of injector cleaner?

Bob Anderson
From my Galaxy S9+ using Tapatalk.
 
#5 ·
Diesel Kleen is usually available at Walmart and it's good. I've used it but have switched to Hot Shot's Secret. Might try their Diesel Extreme.
The Diesel Kleen jug that does 250 gallons all at once or the entire bottle of Diesel Extreme.
May not fix all the problems. But definitely should help the balance rates.

Bob Anderson
From my Galaxy S9+ using Tapatalk.
 
#6 ·
Ya certainly looks like dirty/plugged injectors

Sent from my SM-N920V using Tapatalk
 
#7 ·
Might try searching "ice pick fix".
 
  • Like
Reactions: DaJokr and ieetgluu
#8 ·
I agree...those connections may be getting loose and/or weak.

Bob Anderson
From my Galaxy S9+ using Tapatalk.
 
#9 ·
But if you're swapping injectors and it follows then it's likely the injector

Sent from my SM-N920V using Tapatalk
 
  • Like
Reactions: rta1197
#10 ·
Thank you all for the replys. I will pick up some injector cleaner this afternoon. I tried the ice pick on the plug ins on the affected plugs and no change. The injectors I swapped were from a running core motor with a bad crank, so I am not sure if they were in fact good. To see no deviation in the ones with the return rates pegged at 15 (cyl 3 and 6) is what had me questioning a circuit problem and etc. I also checked the FICM harness so see if there were any rub areas and they was not any. Thanks again for the quick replys.
 
#12 ·
Could be injectors but if it's not running right you can't get a good read on balance rates.
 
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