[eabrust]

A little more of an update regarding my issue and fix with the non-IH strategy FICM tuning, as I had bounced some emails back and forth with Bill regarding my truck about a month ago, and had told him I planned to update this thread once I got it sorted out for good.

Initially, I had bought a pair of injectors, and had only replaced the one injector that a shop told me was bad via contribution test (keeping the other as a spare for a rainy day). When I replaced the one suspect injector, I found the screens on the fuel side were busted up and injested into the injector. After replacement of that one injector, my truck was running great at startup (no stutter/miss) for about a week.

After the week (and a subsequent long trip on which the truck ran great and I got darn near 20 mpg), it was time for an oil change. So I dumped the 5-40 synthetic I had in the truck, and replaced with conventional 15-40. The very next morning, truck was running like poo again, and the Gryphon threw a cylinder contribution fault on another injector (first time I had ever gotten this fault from the Gryph.) So I did some messing around, and could turn the problem on/off again by swapping stock Ford FICM back in and out.

In went the other new injector, again I found this next injector had the screens busted up. Next startup after the second injector replacement, found the truck running better, but still missing a bit, and the Gryphon showed a cylinder contribution fault on yet another injector! Talk about PO’d and frustrated. At this point I could have probably just put in synthetic oil and been done, but I decided that was just putting on another band-aid.

So this past weekend, I finally received another 5 injectors and replaced all the remaining injectors (1 injector was replaced about a year ago under warranty, hence the 2+5 equals the remaining injectors). Out of the 5 last injectors, every one of them had some level of damage to the screens on the fuel side, with the contribution fault offenders having the majority of all 3 screens gone. I’m not sure what the culprit to the screens is/was, as I’ve measured my fuel pressure at ~55 psi. If I had to guess, probably cavitation of the fuel as it passes through the screens, or the screens just finally fatigue out due to getting hammered with pressure pulses for billions of cycles?

Long story short again, my truck now starts and runs awesome from the get-go on 15-40 oil, as it should. This has shown me that:
1) These injectors take very little to upset, IH strategy and synthetic oil are both ways to mask an issue that may not even be on the oil side.
2) The truck must be unable to throw a ‘cylinder contribution fault’ on multiple cylinders, as it wasn’t till I replaced the initial ‘really bad’ injector that I started seeing other cylinders faulting.
3) I’ve pulled apart several of these injectors, and I really don’t see issue on the spool valve side, I suspect that the debris on the fuel side upsets the hydraulic force or amount of plunger stroke required to get adequate fuel delivered (once the debris gets in there), and once the truck is warm and both the oil and fuel viscosity drop, the problem is less apparent to the point of being un-noticeable.
4) The Gryphon ‘Load’ PID is a good reference for trouble shooting also. When I was starting my truck w/ bad injectors, I was seeing a load of 60-75% while the truck was just sitting and idling, and it would drop to 25-30% when warmed up. Now, with all injectors swapped, I see maybe 30-40% at intial startup, and it hovers around 20-25% when warmed up and idling.

I’m going to stay w/ the non-IH strategy FICM, as it has proven to be a really good diagnostic tool. If I had pulled all the injectors out and found nothing but ‘sticky’ spool valves, I’d rethink that. But I tried the oil additives for stiction (Hot Shots Secret, etc) and they didn’t work (but to the credit of the vendor, I received a full refund-Not advertising for them, just stating the fact). Since I found what amounts to a mechanical failure with the screens injested (at varying degrees) on all my injectors, I’m pretty happy this finally motivated me to fix the issue the proper way.

Just hoping this helps out others having issues, as I was of the opinion that I needed to have IH added to my FICM tune. It would be really interesting to find out if there is a fair number of trucks out there that IH tunes help, but really, the inejctors have eaten the screens in a similar manner to my truck.

Regards,
Eric