P0278 - Cylinder 6 balance fault.
P0306 - Cylinder 6 misfire detected.

Some Possible issues:
* Bad injector.
* Valve damage.
* Hydraulic Lifter/rocker/cam damage.
* Cylinder head gasket damage.
* Cylinder head damage.
* Piston and/or cylinder damage.
* Piston ROD damage.

Washing the cylinder - piston is not possible, diesel fuel is OIL.

.

__________________
ASE Master Mechanic
asemastermechanic@juno.com

Prototype R&D/testing:
Thermal & Aerodynamic System Engineering (TASE) Senior vehicle instrumentation technician.
Noise Vibration and Harshness (NVH).
Dynamometer.
Heat exchanger durability.
HV-A/C Climate Control.
Vehicle build.
Fleet Durability
Technical Quality Auditor.
Automotive Technical Writer

1985 300SD
1983 300D
1984 190D
2003 Volvo V70
2002 Honda Civic

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