Well, it's been a long time since I posted an update. Life has been kinda crazy and I've had little time or energy for working on the camper. But... I seem to have finally solved a long running issue with my engine and figured I'd share.
It's not often that a repair on a Ford 6.0 is "cheap" so if you're chasing engine codes around then you might find all this helpful.
Starting a couple years ago I was occasionally getting a check engine light with a P0299 error code (low turbo boost). Sometimes if I was hitting a particularly steep hill in hot weather or making a high speed pass the darn thing would go into limp mode and I'd have to pull over and do a restart. Once in a great while I'd also get a P0478 code.
Since my ambo is a 6.0 this was fairly terrifying as all the stories of them blowing up came rushing into my head. It didn't show any signs of the usual failures and ran fine as long as I didn't put my foot into it.
Recently though it's been getting a lot worse to the point I'd have to turn cruise control off on the hills to avoid it going into limp mode and it was definitely low on power.
I finally got around to programming the custom 6.0 gauges into my ScanGauge and began working my way through a real diagnosis. Despite all the weird things the only issue that showed up was the FICM (fuel injection control module) was showing low voltage.
Now, anything under 45 volts is considered a bad unit and mine was down to 38.5 volts when starting. Oddly though, I couldn't find any documentation that this would cause the error codes I was getting.
A rebuilt FICM is about $500 minimum plus a core charge. However, a friend put me onto the fact that it's usually only the power supply that fails, and those can be had for a bit over a $100 bucks.
This may be one of the few jobs that's easier on an Econoline than an F series. Instead of being mounted on the engine, the FICM for the vans is mounted on the driver side fender. Only had to move the coolant reservoir and the air cleaner out of the way. The entire job only took about an hour. This included getting the FICM open, replacing the power supply board and putting it all back together.
Started it up. Checked the FICM voltage. 49.5V. Way better! Went for a test drive. Flogged it hard. (which usually went put it into limp mode) Full throttle to 75mph. Hit 25lbs of boost and no codes and no limp mode. Definitely the best it's run in a couple years. I'd forgotten how quick it is despite weighing 9600 lbs.
Moral of the story? Modern diesels are complicated. There's a crap load of sensors and a long, long list of things that can go wrong. However, with some inexpensive tools, a lot of reading and a bunch of patience and there's a lot you can figure out. It's way better to invest the time diagnosing than to start replacing parts based on diagnostic guessing. I almost resorted to that myself... even my mechanic buddy that owns a 6.0 and has worked in a Ford dealership thought it was more likely the turbo vanes were sticking.
Here's the link to the ScanGauge 6.0 page:
https://www.scangauge.com/xgauge_collection/ford-6-0l-diesel/
