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Jeremy, Certified Truck/Bus Technician
Category: Medium and Heavy Trucks
Satisfied Customers: 3319
Experience:  ASE Med/HD Truck Technician, NATEF Diesel Engines and Electrical/Electronics Technician, EPA 608/609 HVAC Certified, Steering/Suspension and ABS/Brakes Technician
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I have a 2004 Ford F350 Superduty 6.0L that is blowing smoke

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I have a 2004 Ford F350 Superduty 6.0L that is blowing white smoke whether the engine is hot or cold. There are no codes, it runs terrible while the exhaust smells like raw diesel fuel. The truck has all new injectors, a new EGR Valve, a new EGR cooler, a new oil cooler, new intake manifold gaskets, and a new FICM. Can you give us any ideas on what it could be, or where to start looking?

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You are describing ons of the injectors on the truck being faulty or an issue in the glow plug system. What throws that off on the glow plug system is the issue is still occurring when the engine is hot which is telling me that one of the injectors you have installed is a faulty injector.

I would do a buzz test to see if the injector will code followed by a injector cut out test with the Ford software. There are many times I have gotten new injectors to resolve an old injector issue to have one of the 8 be bad and have to pull them all again for testing, especially if any of them are rebuilt or are Allied brand injectors.


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Customer: replied 10 months ago.
We have run the injector cut out test and all injectors are working with no codes popping up.
Customer: replied 10 months ago.
What avenue would you go next?

I would then check the FICM SYNC then procedd to a possible intake issue to see if there is over fueling with not enough air from the turbo. With that I would start with the exhaust back pressure sensor and tube to make sure they are both clean. Then I would check the turbo for spool up and maybe even pull it, crack it open and clean it in case the vanes are sticking.

CLICK HERE for the steps to do the turbo cleaning.

This is all of course based on the injector tests passing and the FICM programmed properly with no codes or oil pressure issues.

It could be a simple injector defect issue, but the injector company will want the other items ruled out before they warranty them.

Customer: replied 10 months ago.
hi. this truck was smoking slighty with a ficm code. Replaced the ficm but no change. Found the egr cooler to be bad so that got changed with the oil cooler. At that time we cleaned the turbo. Then we found the head gaskets bad and sent the heads out to check them and resurface. At that time we installed rebuilt injectors. All the time still smoking raw fuel. Ficm sync is yes.

Buzz test passes? Injector harness tests good? Programming is correct and all software revisions match?

I see you viewed this and this is still showing as a open question due to no positive (3 stars or more) rating.

Did you still need assistance with this?

Customer: replied 10 months ago.
This truck smokes like it's killing bugs. I've worked on these for many years in my diesel shop and never had this problem. I unplugged the ICP and clears up perfectly. Plug it in and a minute later bellows of smoke. I noticed the timing plugged in when hot is minus 11. With the ICP unplugged it is minus 4. I'm thinking bad ficm bad ecm bias sensor or bad wiring. Any idea which sensor could do this?

It clears up when you unplug the ICP? What is your oil pressure reading on the rail with a manual gauge? I'm presuming the ICP is a new sensor?

What is the voltage coming off the FICM?

Timing is typically related to the CMP and CKP sensors. Are they showing in SYNC? It sounds like one is out of SYNC with the FICM or all 3 might be out of SYNC. It is odd that you have them all in SYNC, but the timing goes way off. That makes me wonder if there is a PCM issue or programming loss concern. I've only had that hapen to me twice in my career and both times I had to replace the PCM when everything showed in SYNC but the timing adjusted that much off.

Customer: replied 10 months ago.
Haven't checked rail pressure manually. Ficmlpwr 13.0. Ficmmpwr 48.0. Ficmvpwr 13.5. Ficmsync yes. On my snapon souls I have another that is just sync. That is also yes. I did have the cam and crank sensors unplugged when I pulled the cab to replace head gaskets.

You have those sensors plugged back in? They show a sync when cranking as well?

Customer: replied 10 months ago.
I haven't forgotten you. I did find a code in the transmission. P2552. Diagnosing that. Will get back to you.

You have a short in the harness between the FICM and the PCM per that code.

P2552: FICMM (fuel injector control module monitor) Circuit-Throttle/Fuel Inhibit circuit

Signal Function:

The diesel engine power monitor (DEPM) strategy resides in the transmission module (TCM) located inside the powertrain control module(PCM). The function of the DEPM is to monitor the engine RPM when there is no power demand from the accelerator pedal position (APP) sensor.
Under normal engine idle operation the DEPM RPM value must always be higher than the engine RPM. In the event that the engine RPM does not exceed the DEPM limit, the DEPM disables the crankshaft and camshaft output signal sent to the PCM to the FICM.


The FICMM input line informs the diesel engine power monitor (DEPM) when the injectors are turned on and off. When the FICMM line is either shorted or open, the monitor strategy assumes that the fuel injectors are always turned on and sets DTC P2552. When P2552 is set, the DEPM may set DTC P0148. When DTC P0148 is set, DTC's P2614 (CMPO failure) and P2617 (CKPO failure) may also set. If DTC's P2614 or P2617 are set with P0148, do not attempt to diagnose the CMPO or CKPO circuits. DTC's P1378 or P1379 (FICM voltage) may also cause DTC's P2552, P0148, P2614 and/or P2617 to be set.

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Customer: replied 9 months ago.
Well I got the truck running great. After testing the harness all showed good. One of my mechanics said that the international buses where he used to work would come in smoking and they would reprogram the PCM so we tried it. It worked. All I can think of is the new injectors we put in we're for early 6.0l. Now this truck is a 2004 with early high pressure pump but later oil manifolds. Been told Ford updated some like this. Maybe the PCM tried to learn the old style injectors. Any way thanks for the help.

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