Got bored this afternoon and decided to play with the stroker and did a CCT. It returned a 0278 fault. Checked the manual and it went straight to rods, rings and everthing internal. After an evening reading here I notice that usually it ends up being an injector. But could a flaky PCM cause a contribution test fault also since it is tasked to drive the test.

History - p0344 - CPS replaced, code still there, look for short in harness, replace engine harness, code still there, look for short in PCM/IDM harness, replace that harness, code still there.(this is where I am now on this one), next step replace PCM.

p0107 - cleared and has not returned but the only step in the manual if it returns is replace PCM

P(something i cant remember),cleared and has not returned, but step two was replace PCM and I ruled out step 1.

Truck has 83K on her, does not smoke a bit or use any oil, runs smooth and has same power as when new, no knocking and fairly quiet for a stock fuel system. Been running 16oz DK to every tank since I learned about it here. All of this has been going on for the last 2 months and everything seems to be pointing to a PCM that I will be ordering next week. But should I ignore the 0278 and retest after the new PCM is in or should I go ahead and get a blowby and compression test done quickly.

 

Your first assumption would be correct for no oil use and no blow by. You can norrow your search a little bit by pulling the engine wiring harness and checking for ohms less than 4. Pull this at the module that is behind the fender well on the drivers side. Doing this step pinpoint test will eliminate 2 other pinpoint tests. This will check the wiring from the icm to the injector and rule out wiring or spring up the gasket harness is too loose. Then, its either the injector may have just obstruction that you cannot tell when running or its the pcm.

 

P0278 Cylinder 6 Contribution/Balance Fault


sounds like a chafed UVC wire or something that is causing it to ground on the valve cover and not fire the injector. any abnormal or engine-related vibrations when running?

 

Yes. They have a tendancy to fall out of thier plugs on the inside of the valve covers.
I took some pictures when it happened to me.

https://www.ford-trucks.com/forums/2...or-wiring.html

.

 

very nice pictures and thread. i left some points

 

Strokin_it - every harness under the hood except the UVC is brand new less than 4 weeks old. I thought that I should get a litttle rough running if were the UVC she idles and runs as smooth as ever?

Kennedyford - i never thought about ohming it from the IDM connector guess the obvious escapes us sometimes. I guess i could use the old harness to build a UVC breakout pigtail too.

Kwik - found your thread last night before I posted but like I said above shouldnt i have some ruff running?

One thing i'm going to look at today is take a 20 mile interstate drive and data log the rotational velocity for all of the cylinders to see if # 6 or another is a little out of range. Thanks for the input so far will keep posted.

 

OK back from the drive #6 is showing ~5% change at idle only, any throtle an it goes to 0.0. BUZZ test indicates all OK and harness ohmed at < 4. Here is an AE view after I got back

At Idle:

A Little Throttle:

More Throttle:

 

Another note/thought: When cold cranking ICP pressure reads ~570, once the oil reaches operating temp it will run ~470. when I first cranked it this am and looked at rotational velocity it was 0.0 across the board at idle. Only after bringing the oil up to operating temp did the ~5% change on #6 start.

Right now i'm leaning toward injector replacement, Any other thoughts or possibilities

 

Another thought if it wer rings/rods ect. wouldn't itget worse with throttle?

BTW I use Delo400 and about 3K on the change, Fuel filter changed at last oil swap but it was not very dirty.

 

Ummm, can you tell me what program you are using to run down the road and monitor your engine? I would really love to invest in that, it looks like you run off of your laptop. Is this correct? How much would it cost me to purchase?

If it were your rings, not rods, your amount of oil usage would be high or you would have oil leaks because the amount of crank case pressure would blow out other seals. You dont have enouph miles on your engine or super high performance to lead to bad rings. I have 450k miles now and just changed injectors.

 

www.autoenginuity.com

379 for the enhanced ford package

Dennis at ITP has it for the same price and he has a forium dedicated to it

 

my manual stated this:

P0278 —
curcuit index- PCED (powertrain control engine diagnostics)
condition description- Cylinder 6 contribution/balance fault
Probably causes- Power cylinder, valve train or injector problem, circuit


my guess is that the injector is faulty.

 

Strokin - thats kinda the way i am leaning but the "other items" in the repair manual for 0278 worried me (ring, rod, ect) and i wanted to hear some other opinions. all injectors passed the buzz test and the uvc ohms out <4 sitting in the driveway (still could be an intermittant but thats gonna have to wait for a visual). Are there any other test you know of before i crack the VC

 

Updateing with solution......A Carquest CPS was causing all the trouble. Put in an OEM I got off EBay and everthing returned to normal. The Carquest CPS was not bad it was just "off" enuff to throw the timing way off and cause the CCT imbalance and generally run like crap.

 

I had the same problem with a Carquest CPS. When Ol' Blue was all the rage I went out and bought one. Replaced my Carquest CPS. Truck ran better. After more info about the blue CPS came out, I replaced it again with a black CPS from International. Truck ran great. I'd stay away from aftermarket for the CPS. Way too risky. Good to hear you found your problem Alan.

Duncan