6.0L PSD Miss Diagnosis

Caver Dave

Caver Dave

Just holdin' it down here in BFV
Moderator
Joined
Mar 10, 2005
Location
Hooterville (24171)
2004 "late model" 6.0L... 108K
Recently deleted, new Ford oil cooler, rebuilt #1 injector, fresh oil (Rotella T6 5W40) & Motorcraft oil/fuel filters

Noticeable miss/extra clatter when cold... miss comes & goes when warm.
Repeated logged codes "Cyl.#7 balance & contribution" (cleared and will return).
Buzz & contribution tests with a Nemesis all passed...
No idea what the fuel pressure is, but do know the steel fuel tank (C&C) is de-laminating from debris found in the HFCM "primary" fuel filter (tank will be addressed come spring)... FP gauge & blue spring on the way

So, I've read & been warned that regular contribution tests won't necessarily pinpoint *bad* injectors due to the FICM compensation (basically good injectors being over-fueled/driven to compensate for a bad injector), so the ability to run a "non-compensated contribution" test is the best way.
Anyone local have a scanner with that ability?

Have also read that marginal FICMs will also cause sporadic missing, even if the voltage isn't in the 45V "danger zone" (mine runs 47.0V, with occasional dips to 46.5V-46.0V)??

Question for all the 6.0L gurus... where would you go first?
 
If its regularly throwing a #7 contribution code that's your most likely bad injector. Worst case if you're not local to any independent shop with the right scan tool such as I fix Ford s in fuquay then a Ford dealer could run the test for you then you decline the work and fix it yourself. I'd say it's most likely the injector followed by a ficm. Since it comes and goes and worse cold, its likely not a mechanical issue such as compression. Those are classic signs of injector sticking. I have auto enginuity but it won't disable the compensation so it only really works on regular misfires.
 
1 - If you throw your hands up, call Scott at Trucks Unlimited. one of the best PSD mechanics in the country, in your back yard, and cheap.
2 - I'll give you a test that will likely prove out your issue. Change the oil, with TG1. 15-40 Dino. I bet the cold issue goes away if not the entire injector completely. Now Id still run T6 or T5 for other reasons, but 6.0 injectors are finicky on the full synthetic. Well they are finicky period, full synth seems to exacerbate it. Internet legends point to the full synthetic having a lower viscosity and not building enough cold pressure in the HPOP. Ford engineers say that lacks merit.

#7 is pretty common web failure. Some claim the blue spring improves it.
 
Change the #7 injector its starting to go bad and after you swap the injector run a dino 15w 40. Synthetic is no good for the hpop system
 
Check batteries and alternator.

Easy to do and it gets you at the beginning of the electrical system components which are known to be problematic and cause issues to the FICM and injectors.
 
Thought I'd post the follow-up/results... for @cass92lx50 (Seller... Thanks again sir!), @Ron, @rockcity, @Tim C & @toyota1 (web diagnostics & TU referral)

The miss got a wee bit worse and didn't go away at all when warm.
Added some Archoil 9100 which really did help the cold noise/clatter, seemed to start better, but didn't do anything for the miss.

Since I was worried about the tank delaminating and causing fuel pressure issues, a few weeks back, it got yanked (absolutely spotless... ZERO signs of the liner, rust, anything), and reinstalled after blowing all the lines from engine back.
I now believe the injector issues were caused by a combination of the tank delaminating (mid-filter had a handful of lining in it), and crappy maintenance.

Dropped it off Scott @ Trucks Unlimited on Tuesday evening. He called Thursday with the diagnosis... #7 injector completely dead, #4 injector firing 30% cold-50% warm (basically running on 6.5 cylinders), GP module inop, #8 GP, and low FICM voltage. So, the parts tally was 2 injectors, GP module, 1 GP, FICM board, and install the Blue Spring kit I'd had for a couple months

Gave him the go ahead and picked it up late Friday, a couple days early, despite his entire lot being full (had to park it down the road when dropping it off!). Aside from the wallet ding (which was less than his quote), totally pleased... runs GREAT now! :driver:

Put about 300 miles on it this weekend, and appears MPG will be way up (Tank#1 - 10mpg, Tank#2 - 14mpg). Saturday, I retrieved my #2500 trailer and hauled about 1500# of wood back to from White Cross... neither were noticeable load wise, but it sure rode a LOT better! Now ready to continue "rejuvenation" efforts!
 
Glad you got it figured out

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