Year/Make/Model: 2008 Mazdaspeed 3
Mileage: 109K
Location: San Francisco
Concern: No Power under load
DTC's: P0300 Multiple Random Cylinder Misfire
Modifications: Air Intake, Coilover.
ECU/Tuning Software: Don't know
Tuner:
Is the concern intermittent? No, it's always there
Can you duplicate...