Hi all, I own a 2003 Audi A4 (B6, 3.0, Quattro) and the check engine light was blinking. I put on the code reader and I got engine codes P0300 - P0305. This means that 5 cylinders are misfiring. P0306 did not show up which means one cylinder is not misfiring. The car itself stutters quite a bit when accelerating and shifting between gears. I was wondering, should I replace my air intake filter, my mass airflow sensor, the spark plugs, or the coils? I figured it wasn't the plugs or coils because it's not likely that 5 out of 6 coils misfire; it's probably a sensor error. If you know another solution please let me know!

 

A vacuum leak can cause multiple misfires.