racorcey
05-23-2014, 10:53 AM
I happened to see this in this month's issue (May, 2014) under Service Slants. Veddy interesting:
Ford
No power, rough running, MIL illuminated with misfire DTC(s) stored. Owners of some 1999-2005 Ford-built cars and light trucks with the 4.6 or 5.4L four-valve engine may come into your shop with complaints that their engine is down on power, runs rough or misfires while driving on the open road.
According to Ford, the driveability symptoms are most common on vehicles built before 12/19/04, will typically be accompanied by an illuminated MIL and will store DTCs P0301 through P0308 and/or P0316 in the PCM. One likely cause, says the carmaker, is gas leakage past the exhaust valves. Installing an improved cylinder head on the affected bank is the recommended fix.
To make an accurate diagnosis, perform a relative compression test on all cylinders. If any show low compression, do a cylinder leakage check while listening for a hissing noise from the exhaust pipe. If you hear the hiss, replace the affected cylinder head with the upgraded unit.
Vehicles that are prone to the issues mentioned are 1999-2004 Lincoln Navigators, 2002-03 Lincoln Blackwoods, 2003-04 Ford Mustangs and Mercury Marauders and 2003-05 Lincoln Aviators. Here are the part numbers for the replacement cylinder heads:
Engine, Cylinder Head Part No.
4.6L, Left . . . . . . . . . . 2C5Z-6049-BAB
4.6L, Right . . . . . . . . . 2C5Z-6049-CAB
5.4L, Left . . . . . . . . . . YL7Z-6049-EA
5.4L, Right . . . . . . . . . YL7Z-6049-FA
Note: Although the cylinder leakage can occur on either bank, Ford says it’s much more common on the left-hand cylinder head. When installing the updated head(s) also replace the timing chain tensioner and pipe plugs.
I wonder if anyone got stuck having to do this to their car yet?
Ford
No power, rough running, MIL illuminated with misfire DTC(s) stored. Owners of some 1999-2005 Ford-built cars and light trucks with the 4.6 or 5.4L four-valve engine may come into your shop with complaints that their engine is down on power, runs rough or misfires while driving on the open road.
According to Ford, the driveability symptoms are most common on vehicles built before 12/19/04, will typically be accompanied by an illuminated MIL and will store DTCs P0301 through P0308 and/or P0316 in the PCM. One likely cause, says the carmaker, is gas leakage past the exhaust valves. Installing an improved cylinder head on the affected bank is the recommended fix.
To make an accurate diagnosis, perform a relative compression test on all cylinders. If any show low compression, do a cylinder leakage check while listening for a hissing noise from the exhaust pipe. If you hear the hiss, replace the affected cylinder head with the upgraded unit.
Vehicles that are prone to the issues mentioned are 1999-2004 Lincoln Navigators, 2002-03 Lincoln Blackwoods, 2003-04 Ford Mustangs and Mercury Marauders and 2003-05 Lincoln Aviators. Here are the part numbers for the replacement cylinder heads:
Engine, Cylinder Head Part No.
4.6L, Left . . . . . . . . . . 2C5Z-6049-BAB
4.6L, Right . . . . . . . . . 2C5Z-6049-CAB
5.4L, Left . . . . . . . . . . YL7Z-6049-EA
5.4L, Right . . . . . . . . . YL7Z-6049-FA
Note: Although the cylinder leakage can occur on either bank, Ford says it’s much more common on the left-hand cylinder head. When installing the updated head(s) also replace the timing chain tensioner and pipe plugs.
I wonder if anyone got stuck having to do this to their car yet?