Ford 7.5L 460 loss of power when hot

weschaney wrote:
Hi guys, i just acquired a 1991 27' fleetwood class c rv. It sat for about 8 years before i bought it. I've since drained the old gas, new fuel filter, trans flush, motor flush and new battery. It fired up and ran like a champ for about 300 miles. Now I'm having a issue where after driving for about 5 miles and reaching running temperature it bogs down so bad it won't down shift and will eventually stall if you try to accelerate at all. After it sits over night it runs strong, for about 15 min.. then gradually bogs down till i have to pull over. revs fine in natural, so this is a issue under load. I took it to a trans shop, they said not a trans issue in their opinion, feels like a clogged cat to them. i removed the cat, still has has the same problem. any ideas?

THANKS FOR ANY HELP!!

Your engine most likely has the notorious Ford TFI (Thick Film) ignition system which is well known for STALLING, DIEING AND SPUTTERING and other drive ability issues WHEN HOT..

Also well known for wiring randomly grounding out..

HERE is some helpful info on the TFI ignition systems..