FICM Voltage Behaviour

[Penhall]

Did a lot of reading on FICM voltage issues but couldn't really get a good answer on one thing. Does the voltage drop/fluctuate with temperature. (oil viscosity too I guess).

Lately been about -30c around here and have had the truck plugged in. Last week let it sit for few days then plugged it in for 5 hours - no start and the batteries were dead. Recharged for the day and it fired up.

Next day, start up and go for a burn - after a couple miles starts running rough, no power so pulled over. Cleared itself up in about 30 seconds and then ran fine.

No CEL but code P0275 (cylinder 5 contribution/balance) was present. Has run fine since.

Checking FICM voltage via the Edge CS and the Key On/Engine Off voltage is fine @ 48.5 volts. Fire it up and drive then it drops to around 30V and progressively gets better as the engine warms up until its back to ~48V at idle but drops under accelleration as power is put to the injectors.

Is this normal for FICM voltage?

I've always thought my truck billowed a lot more white smoke in this type of cold than other 6.0l so still suspect that injector 5 might have always been wonky and you can hear the 'miss' from that bank on initial start so I'll check that anyway. Seems to be more of a tinge of blue to the white smoke too and possibly some raw fuel out the tailpipe (which I previously thought was just condensation).

Insights, suggestions before I talk to my usually wrench-pullers later?

Thanks
George

[2 Stroker]

Your FICM is toast send it in to Ed, anything under 45v anytime (going bad).
http://ficmrepair.com/ My choice
Plus you need to get some new batteries 850CCA then see what you have
2 stroker

[Penhall]

I'm suspecting the FICM too but perhaps was wanting someone to say that its normal ;-) behavior in the cold.

Batteries are actually 3 month old Ford OEM 850's

[2 Stroker]

You need a Syn 5w40 oil use Ford or Racor filter only and if plugged in it starts better and your FICM is under 45v its bad. Pull it and send it in to Ed. If you need to call him his number is in the link.
2 stroker

[Penhall]

Yeah, I've dealt with cold weather operations for years, no issue with the oilweight or filters (Ford only), batteries, block heater, battery blankets etc.

I've just never watched the FICM voltages before so wasn't sure with fluctuations.

Thanks

[ford_doctor]

Penhall, the varying FICM voltage you describe is not normal and it is indicative of a failing module. A good FICM should hold voltage steady withing 1V during any condition. The drop to 30V is way below specification and as recommended you should repair or replace it before it leaves you stranded. I have observed this very behavior when diagnosing FICM's many times over the years.

[Penhall]

Perfect thank you. I'm definitely going to replace it now as I can afford the time to park the truck for bit to get it done. Strange that it didn't throw any codes though (other than probably taking out the one injector)

Cheers all.

[mjsti]

I've recently replaced my ficm with a rebuilt unit from ficmrepair.com. Got the upgraded version, with 2 yr warranty, and the atlas 40 tune. The truck drives a lot better now, smoother acceleration, plus the extra power is nice. Holds 47.5-48.5 volts during all conditions.

[Penhall]

was also thinking about the 58v version from Swamp Diesels too... a bit more dollars but since I've sunk all this money in already.... ;-)

[2 Stroker]

Not worth the headache, 58v are 2 high
2 stroker

[Iam4MSU]

I just had Ed repair my FICM and added the Atlas 40 tune. My fuel mileage has increased by about 3-4 MPG. I average 21.9 MPG today at 65-70 MPH. Overall average for the last 4 days with 1000 miles hwy and 75 city was 20.3 mpg. I am running Rotella T6 synhetic for the first time with 111k on the clock. I just replaced the EGR and Oil coolers and cleaned the EGR valve and boiled the intake. Added the Blue Spring Mod as well. I believe the FICM was my greatest improvement. Call Ed he will help you and will not recommend the 58V upgrade.

I am happy as a lark about my latest repairs.

PS: I am also using the Ford MC Cetane boost. 4 oz to 25 gallons

[2 Stroker]

Originally Posted by Iam4MSU

I just had Ed repair my FICM and added the Atlas 40 tune. My fuel mileage has increased by about 3-4 MPG. I average 21.9 MPG today at 65-70 MPH. Overall average for the last 4 days with 1000 miles hwy and 75 city was 20.3 mpg. I am running Rotella T6 synhetic for the first time with 111k on the clock. I just replaced the EGR and Oil coolers and cleaned the EGR valve and boiled the intake. Added the Blue Spring Mod as well. I believe the FICM was my greatest improvement. Call Ed he will help you and will not recommend the 58V upgrade.

I am happy as a lark about my latest repairs.

PS: I am also using the Ford MC Cetane boost. 4 oz to 25 gallons

SWEET Great post, Eds the man
2 stroker

[Iam4MSU]

Thanks again 2 Stroker

[Grewells]

just jumping on the band wagon too. I had to replace my FICM as well. Sent it to Ed. i asked him about the 58v upgrade and he sternly advised against it.
My FICM had two (of four) bad power supplies. He fixed those and added the Atlas 40 programming from PHP. Same results as above with mileage and greater low end response (seat of the pants).
One other thing I did do under Ed's advice is replacing the crappy stock alternator with an upgraded one from DCpower. Ed told that is what probably helped zap my FICM. No worries now!!

[Penhall]

Talked to a few others too and they've recommended against the 58v also so going for the standard repair.

And yup, I run the Ford Cetane Boost in summer and the Cetane/Antigel here in the winter, every tank.