Hey all...

First off, I have a 2003 7.3 Auto, 80K. Mods are 6637, HX, Wicked Wheel and FPR shim (had the shim in for 500 miles before problem started). Just recently, I have had a strange problem that occurs at random. I start the truck, it runs fine for a few seconds, then it starts to run rough... like one cylinder isn't firing... I put it in drive and step on the throttle, and there is no power... with a puff of blue smoke out of the exhaust. It starts knocking loudly, and then it stalls. I let it sit for a couple minutes, and start it again and it runs fine. This has happened on two seperate occasions, with 200+ miles of smooth starting and running in between. The first time it happened I was very low on fuel. I limped home, put 5 gallons in the tank, and it started and ran fine. The next morning I filled the tank and it was fine, so I chalked it up to running out of fuel... until tonight when it did it again with a full tank.

I have searched the forums on this topic, but have not found any complaints that match my symptoms exactly. I think that it is getting starved for fuel, because of the knocking... and the closest thing I have found in my searches is the issue in the 99-01 issue with the injector harness coming loose... is this still a problem in the later models? Is my fuel pump crapping out because of the FPR shim? The shim is very mild, only .050 in. Any ideas would be greatly appreciated.

BTW, I am the head mechanic in a Volkswagen in a dealership in Massachusetts, so I am very capable of working on my rig myself... but I have only had this truck for 6 months so I am still learning about the engine.

Thanks in advance...

 

sounds to be injector problem,electrical or injector itself bur probly electrical

 

Check the connections to the valve covers,,especially the plug for the injectors under the valve covers.. Most likely you will find one partly unplugged....