LLY: Rough @ idle and below 2K

[Gmclbz]

Working on an 04.5 LLY with 115k miles on it, all stock. According to EFI #3 cylinder has a balance rate of +15. Tried icepick method and then replaced #2 and #7 harness with no change what so ever. Also checked harness @ FICM. Does anyone have any other ideas? There is no smoke and no blow by. I am at a loss...

 

[JoshH]

Have you tried swapping the injectors around to see if the problem moves with the injector?

 

[Gmclbz]

Have you tried swapping the injectors around to see if the problem moves with the injector?

I swapped 5 and 7 with no change. Wish I had a tech 2, I know that EFI has issues with DVT's so I'm not real sure which is the problem hole. If I shut off injector 7 with EFI idle doesn't change, which is why I tried swapping 5 and 7.

 

[Schwinn68]

Might check the reluctor wheel to see if it's loose. Any codes?

 

[JoshH]

I swapped 5 and 7 with no change. Wish I had a tech 2, I know that EFI has issues with DVT's so I'm not real sure which is the problem hole. If I shut off injector 7 with EFI idle doesn't change, which is why I tried swapping 5 and 7.

The problem is with DVTs, not balance rates. If the balance rates are showing #3 is having a problem, it is actually #3. Swap that injector to another cylinder and see if the bad balance rate moves too.

 

[Gmclbz]

The problem is with DVTs, not balance rates. If the balance rates are showing #3 is having a problem, it is actually #3. Swap that injector to another cylinder and see if the bad balance rate moves too.

10-4 Will try that and report back...thanks!:thumb:

 

[Gmclbz]

Problem solved, ended up being a bad injector. Swapped them and problem followed. Thanks for the help.:thumb: