no power, wont rev past 2700

[jrinaman]

'99 f550, had this problem before, always in cold weather. truck ran low last week(<1/4 tank) came to a crawl on hill and would not make it to top. coasted to level and it idled fine but wouldnt rev. i added 10 gallon af keroseen and within minutes, it ran fine. drove about 10 miles on kero before filling tank with diesel. ran fine rest of day, evan haulled 7500 lbs, ran fine next morning but at end of day (7500 lbs. removed) it would not rev above 2500 and had no power. ran all week like this, once fuel was low(above 1/4 this time around) i changed fuel fiter, added lucas injector cleaner and some other crap that increases cetane, removes water and makes you grow 2" longer. i let it run for 30 minutes then drove it 25 miles and very little improvement, still no power, revs to 2700 and every once and a while 3000. do i just need to wait longer for it to work? or look for other problems? had this last year and took to dealer, he said idm was bad, 1600.00 for new one, plus it needed flashed and labor costs, ~2500.00 total. warmed up the next day and never had a problem rest of winter. it has never acted up in marm weather. would idm do this? what is and what does the idm do?

[melmount]

it could buty the idm is in the drivers fenderwell, beans diesel will sell you an upgraded one that puts out 140 volts instead of 110 or 120. Its 100 bucks. Theres a core charge if you dont send yours first. You can swap it in an hour.

[01clj]

I would just drive it awhile and see what happens. Not sure why you need it to rev so high I almost never take my 7.3 past 2600 rpms and I pull a 12,000 lbs. camper. If you consitently take it to those higher rpms it will shorten the life of the engine not to mention it has less power at the higher rpms then it does at 2700 rpms and below. Take it easy on the motor and it will last forever.

[jrinaman]

dont usually drive at those rpm's, but was always able to when needed. heavy load uphill with 35 mph speed limit. i am familar with idm mod for 140, just not sure what idm does, so dont want to alter it when i have other issues.

[99liftedstroker]

check your fpr i had the same problum and turned out the nut the holds the fpr on came off and it wasnt getting the right singnal to the pcm good luck