Fuel System/Engine Controls - Driveability Concerns
SOURCE: Mitsubishi Tech Talk Article August 2004TITLE: Driveability Concerns
APPLIES TO: 2004 Lancer Evolution
SERVICE TIP:
The PCM reflash described in TSB-04-13-007 is effective in correcting DTC P0300 random misfires. Freeze-frame data should indicate that the DTC was set at 65-80 mph, with 18-25% load. However, if the freeze-frame data indicates that the DTC was set with VSS at 0 mph, or with a 30% or higher load, or if there are also driveability concerns (hesitation, abnormal fuel trim, etc.), continue diagnosing for other conditions, after reflashing the PCM. Inspect the spark plugs and fuel injectors for a reddish tint that may have been caused by additives or racing fuel, which can lead to the misfire condition.