Join Date: Sep 2008
Location: Oakbank, Manitoba
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 6 Post(s)
Thanked 113 Times in 105 Posts
Feedback Score: 0 reviews
It shouldn't start missing after an oil change. However, other problems do seem to show up at this time. If it the problem stays away, you are probably OK; just be ready for the potential injector failure as this may have been the first warning.
Ford 6.0L Cylinder Contribution or Misfire Fault – DTC Diagnostics
This article applies to Diagnostic Trouble Codes (DTC): P0263, P0266, P0269, P0272, P0275, P0278, P0281, P0284 and P0301, P0302, P0303, P0304, P0305, Po306, P0307, P0308 for the Ford 6.0L Powerstroke.
These diagnostic codes indicate that the Powertrain Control Module (PCM) has detected that one or more cylinders are misfiring and non-contributing. The PCM continually monitors all cylinders for proper operation. If it detects a cylinder is misfiring or not contributing it will store a Diagnostic Trouble Code (DTC) to indicate the misfire and identify the cylinder in question. See the Ford 6.0L Diagnostic Trouble Code (DTC) Index to identify the specific cylinder. It is possible that these DTCs are cause by an engine mechanical problem.
Possible causes for any of these codes include:
Low cylinder compression
Low compression in one or more cylinders can result in cylinder contribution or misfire Diagnostic Trouble Codes. A compression test should be performed to determine if this is the cause of the DTC. Possible causes for low compression include:
Broken compression rings.
Leaking or bent intake or exhaust valves.
Bent push rod(s).
Broken rocker arms or retaining bolts.
Bent connecting rod.
Cylinder head gasket failure.
Low Fuel Pressure or Poor Fuel Quality
Low fuel pressure or poor fuel quality can result in cylinder misfire. You should suspect this if you have received multiple cylinder misfire codes. A fuel pressure test should be performed to determine if the fuel pressure is adequate (40-80 psi). A fuel sample should be obtained and checked for contamination and or water. Possible causes of low fuel pressure include:
Restricted fuel filter.
Defective fuel pump.
Defective fuel pressure regulator.
Fuel contamination (water, dirt)
Improper Injection Control Pressure (ICP) / Oil Aeration
Proper Injection Control Pressure is critical for the proper operation of the 6.0L Powerstroke injection system. Poor oil quality or oil aeration can result in an engine misfire because the injectors are hydraulically controlled. Causes of oil aeration include:
Extended oil change intervals resulting in depletion of anti-foaming additives in oil.
Air present in hydraulic system as a result of recent engine or high pressure oil system repair.
Wrong type or grade of engine oil.
Oil contaminated with fuel or oil.
Faulty Fuel Injector
A faulty fuel injector can result in a cylinder misfire. If other diagnostic codes are present that indicate an injector circuit fault those diagnostic codes should be diagnosed first. If engine mechanical problems and injector electrical circuit problems have been ruled out Ford recommends the replacement of the fuel injector in the affected cylinder. It is important to inspect the injector sleeve inside the cylinder head prior to installing a new injector.