dude, I don't know how bad the low power condition you're experiencing is, but we just had a 550 that absolutely whipped our ass... guy took it to ford for a low power condition... it had an 0087 in the memory. they said "you need a pump"
we put a pump on it, found the turbos were suspect and put turbos on it while the cab was up.
the truck was a gutless turd... it passed EVERY functionality test. ZERO CODES!!!!!!!!!!!! zero pending, zero active, zero in memory... everything verified/tested with IDS. commanded and actual PIDS were spot on, passed the rail pressure test. Throttle valve and egr actuated perfectly from 0-100%. Truck didn't misfire or smoke. We even put a pipe and a race tuner on it just to see if a clogged filter was holding it back. GUTLESS
we swapped EBP, IAT, throttle valve, MAP with known good sensors. hell, we even swapped the ECM!
at my wit's end, I called on a friend of mine who is a service writer.
He said, "put new injectors in it"
I rolled my eyes and went on about how it passed every test, idled and revved clean and smooth as a baby's butt, etc. He said, "been there, done that, it's the injectors"
Told the customer you've got three options:
1. enjoy your gutless truck
2. send it to auction
3. put injectors in it, but no guarantee it'll fix it as every means of diag we've done do not point to injectors
customer said "put 8 in it"
8 new injectors from Ford, and the truck ran perfectly with full power
WTMFF?
learn something new every day. talk about an ass whipping
