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Multiple Cylinder Misfire Or Rough Idle
This bulletin involves rotating all engine exhaust valves, replacing the valve spring retainer
locks with a new design to increase valve rotation at lower RPM, inspecting/replacing the
MAP sensor (as necessary), and decarbonizing the combustion chamber.
2004 - 2006 (CS) Pacifica
2005 - 2006 (LX) Chrysler 300/Magnum/Charger
NOTE: This bulletin applies to CS models built after February 1, 2004 (MDH 0201XX)
equipped with a 3.5L engine (Sales Code EGN).
NOTE: This bulletin applies to LX models equipped with a 3.5L engine (sales code
EGG) except 2006 vehicles equipped with California Emissions (sales codes
NAE) built on or before May 2, 2006 (MDH 0502XX). See Technical Service
Bulletin 18-016-06 dated May 4, 2006 for more information..
The customer may experience occasional engine misfire (rough running engine) during
certain vehicle operating conditions.
In addition, MIL illumination may also have occurred due to Diagnostic Trouble Code
(DTC) P0300 - Multiple Cylinder Misfire. Various single cylinder misfire DTC's may also be
present. If the frequency of misfire is high, the Powertrain Control Module (PCM) may
place the engine in “Limp-In” mode.
The misfire condition may be caused by one or more engine exhaust valves that are slow
to close due to a build up of carbon on the valve stem