Code P 0206 and Rough Starts

[Stratosurfer]

Folks,
97 Tahoe has been starting rough, runs fine after warm. Throwing off Code P 0206 "Diesel Injection Circuit malfunction Cylinder 6."

Any Ideas, my mechanic thinks I need to go to the dealer and have my pump retimed as in a DTC Offset error code, but I don't think this is the problem

In additon to the below data I have a new PMD on the FSD cooler mounted in my bumper. These problems were before I mounted the new PMD and did not solve this issue.

[gmctd]

You're right - that's not TDCO

Engine idling, back the #6 injector nut off 1/2 turn, noting any difference in rpm or smoothness - may need to pull the injectors and have them flow-tested at an Inj Pump shop - #6 is next to last on turbo-side.

Problem is, if you had to go to San Angelo to get that done, that run could 'blow' the inectors out and it'd be running good by the time you got there.

[Stratosurfer]

You're right - that's not TDCO

Engine idling, back the #6 injector nut off 1/2 turn, noting any difference in rpm or smoothness - may need to pull the injectors and have them flow-tested at an Inj Pump shop - #6 is next to last on turbo-side.

Problem is, if you had to go to San Angelo to get that done, that run could 'blow' the inectors out and it'd be running good by the time you got there.

Do you think that running some injector cleaner, Marvel Mystery Oil or other might help? I've used MMO often but don't know much about the other injector cleaners.

[gmctd]

If you're using power service\equiv fuel additive and 2-stroke motor oil, that should 'clean' the injectors as you're driving - a good hard run will do the rest.

But, no, I wouldn't recommend adding any of that stuff to the fuel - that stuff's for gassers...........gassers, patooie!