Hi all and Bill,
I had started the original thread on this topic last year, and it's now so long and messy, I wanted to start another thread to conclude what my issue was, and to hopefully help others out with this issue, and help PHP help others getting tuned FICMs resulting in an issue. I know it has been said that the tuned FICM can bring mechanical issues to-light, but sometimes it is hard to believe without an example.... (ask me why I know
)
My symptoms were that my truck ran pretty darn good with a stock (Ford flaxhed) FICM, and really poorly with the PHP FICM (untill the truck warmed up, then it was great). Since I could turn the problem on and off swapping FICMs, the big assumpion I had was that it was software and/or I/H not working (which still may have been the only difference?).
After lots of reading, researching, trying the 'miracle cure' oil additives, etc, I finally went the route of checking the injectors. While brining my truck into a non-Ford shop for front end work, I purposely put in the PHP FICM and asked them to scan the truck and tell me what they could find regarding the cold idle issue. They gave the truck back and told me the #4 injector wasn't working to well (via power balance test).
Since it was only one injector showing bad, I took the truck back, ordered myself a remanufactured injector (without core charge on purpose...) and decided to replace it and see if it actually worked as a solution.
To get to the point, after pulling #4 injector, I found all the inlet screens on the fuel side of this injector had failed and gotten sucked into the injector, which isn't what I was expecting to see. I put in the new injector, reinstalled the PHP FICM, and now it runs like a top from the second it starts, no more issues till warm, truck just runs great (basically the same as it did with the bad injector and Ford FICM tune, go figure).
So I pulled apart the bad injector for fun and to try and get some justification to the issues I had (
injector work 5-23-10.pdf ) <-- See this, lots of pictures of injector guts!.
What I found is what has me confused. Per the symptoms, the assumption was that the spool valve was sticking w/ oil varnish, as that is what the I/H strategy is supposed to fix. What I found was that the spool valve end had no issue that I could detect (spool was smooth and free, and no varnish/discoloration), and issue was all on the fuel side of the injector (lots of fine wire mesh screen debris sucked in on the plunger side, got alot out w/ solvent flush). Perhaps the I/H Ford strategy had slightly different valve operating durations to make it work, or the I/H heats both the oil and fuel side enough to make a difference?
Long story short, my truck now runs great w/ tuned FICM! (for the last two days, and hopefully at least till winter comes around, then I'll know if I need the I/H...
) So I hope this helps with clearing up the issue a bit for others. I was a firm believer all I needed was the I/H strategy,
I was wrong. I did only pull the one 'bad' injector because of a lack of seals for checking them all, so maybe all my injectors have sucked in screens and this injector alone just needed I/H? Either way, I was just one injector from working good all this time!
Thanks and sorry for being a pain for so long Bill!
Eric