2001 f-450 super duty misfire?

a_kelley

a_kelley

mechanical fixer
Joined
Jan 26, 2010
Location
Rutherfordton
I've got a f-450 7.3L turbo thats missing at low rpms but clears out if you baby it to higher rpm's. partially clogged injector or two? Check engine light is on but I guess ford made it to where you can't just read the codes with a regular economy actron scan tool. Going to bring it by a shop with a $$$ reader and see what it says, but am I about correct its got an injector not squirting properly?
 
a_kelley said:
I've got a f-450 7.3L turbo thats missing at low rpms but clears out if you baby it to higher rpm's. partially clogged injector or two? Check engine light is on but I guess ford made it to where you can't just read the codes with a regular economy actron scan tool. Going to bring it by a shop with a $$$ reader and see what it says, but am I about correct its got an injector not squirting properly?
Click to expand...
Injector and IDM would be the most common issue. It could be lots of things but a decent scan tool will put you in the right direction. Good time to check fuel pressure and ICP pressures. If it's a not a definitive misfire low power can be caused by up pipe issues.
Under valve cover harnesses will undoubtedly be mentioned, if they were the cause you'll have injector circuit codes and a misfire typically at all rpms. If it came in our shop, codes, freeze frame, cylinder contribution test, and then test mechanical aspects. If you have any questions feel free to pm me.
 
Make sure they buzz test the injectors. It being a F450 is the reason an actron el-cheapo scanner won't scan it, its considered a medium duty truck and most smaller pocket scanners do not have the proper protocol for the medium duty stuff. Heck some bigger "badder" scan tools don't read it well.
 
I'm going to check it out again tomorrow.. Not that I have a better scanner to check it with, but I have a notion that the fuel line may be stopped up because I dropped the tank out of it and there was some kind of rubbery type junk plugging the pickup screen (before replacing the fuel pump). Also the pump sounds like it is sucking air or something, like not a constant flow back into the tank when you first turn on the key and the pump runs without starting the motor.
 
Tank delamination. The liners on Fords of this era don't like new fuels or the additives people use, especially alcohol. It chunks off and clogs everything. @McCracken dealt with this during his build. I talked to the guys at King Radiator when they did a gas tank for me. They keep repaired tanks on the shelf. You take yours and exchange.
 
Back
Top