99 F250 7.3L Problem
99 F-250 Superduty 7.3L truck is having problems.
Last February we had a horrific freeze which cause the diesel to gel. It hasn't ran right since. It started out to where you could drive for a ways before it would mess up, now you can't even make it a mile.
It idle's ok and runs ok at speeds up to 20mph ish. After that, it starts cutting out like it is running out of fuel. If you let it set for about 5 minutes, it will start up and run again for a mile or so.
We have replaced fuel filter, and fuel pump with no success. Dropped the fuel tank where we found the sock floating in black gunk. Completely drained, cleaned, blowed the air out of the lines, and filled back up with fresh fuel. Ran really good. Drove it to work (50 miles),ran it at 65-70 mph, ran wonderful. About 7 miles heading back home, it started messing up again, doing the same thing. Thought maybe there was some residual gunk that broke up, replaced the fuel filter again, still nothing. Drained the oil from the high pressure oil pump which was extremely thick, ran 4 cycles of fresh oil in it. and replaced the injection pressure regulator valve....Still nothing.....
Out of ideas but really need the truck back ASAP