Possible Causes
WARNING: This page does not describe the selected car, but rather 9 other vehicles, including the 2003 Ford RV Cutaway, 2003 Ford Pickup, 2003 Ford F550 Super Duty, 2003 Ford F450 Super Duty, and 2003 Ford Excursion. However, it is still accessible from the selected car via links, so may be relevant.
- Broken compression rings.
- Leaking or bent valves.
- Bent push rods.
- Bent connecting rods.
- Damaged rocker arms.
- Faulty fuel injector assembly.
See 7.3L V8 TURBO DIESEL article in ENGINES for engine mechanical diagnostic procedures. If base engine condition meets specifications, injector may not be functioning correctly and will need replacement. Fuel injector solenoid and wiring should have been checked in previous tests.