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2003 7.3 - No power after warm-up
Have 2003, 7.3 E350 with 140K miles. Last fall the truck starting having problems where the engine would completely lose power after warm-up. After warm-up, the truck will run OK if you didn’t give it more than 10% throttle. But, if you try to accelerate more, the throttle response goes completely flat, white smoke pours out the exhaust, the engine gets really “clattery” noisy at idle, and won’t even rev up with the truck in neutral. Turning the engine off for a few minutes then restarting allows me to get back home if I don’t try to accelerate too much. To date I have changed oil and filter, replaced the cam position sensor, exhaust back pressure sensor, rebuilt the fuel filter canister, replaced fuel filter, and replaced the fuel pump. (Two years ago I replaced the HPOP and IPR because of an oil leak in the pump. About 3 years ago I replaced the IDM with a rebuilt unit.)
Just bought a AE scanner and after resetting the trouble codes that I created in the past by disconnecting various sensors, there are no error codes being generated when the problems exists. All self-tests pass except for one, cyl 4 high/low failure. However, cylinder 4 sounds fine in the buzz test. If I data log various sensors, nothing seem out of ordinary (injector oil pressure is approx 575 psi at idle and follows throttle position sensor to 2800 psi if I rev the engine. (IOP duty cycle looks fine.) Exhaust back pressure looks fine. The only thing that looks like a problem is the fuel injector pulse width. The AE range for this pulse width is 0 – 58 msec. My reading seems to be around 0.28 msec. This reading changes slightly with engine rpm, but not more than 0.05 msec around that value. However, no matter what sensors I look at, none seem to change when the problem happens. Anyone have any suggestions?
Last edited by Caveman807; 02-22-2014 at 04:22 PM.