misfires

Year/Make/Model: 2009 Speed 3 Mileage: 105K Miles Location: Charlotte, North Carolina (sea level) Concern: Spark advance is high, engine is misfiring and running hot DTC's: P0300 P0403 (EGR) U2064 U2619 Modifications: Cobb FMIC, Cobb BOV, Cobb Turbo Inlet + Intake + Airbox, Cobb Boost Control...

2012 Mazdaspeed 3 52,000 miles no mods no tuning I've replaced the HPFP, both o2 sensors, spark plugs, fuel filter, air filter, and front cat. The symptoms have not changed. I bought this car about 6 months ago from an elderly woman whose husband (this was his car) just died. The car will run...

I’m having what seems to be a very common issue talked about here but I have searched for several days to find a fix an I can’t seem to find anything that helps Some background, I’m a mechanic. I’ve been working on cars for a few years now at a shop an know about engines an how to solve issues...