Misfires Under High Load in European and Japanese Vehicles

Some high-performance vehicles, including certain Mercedes-Benz, BMW, and Audi models, may experience misfires under high load. This issue can be accompanied by a check engine light and typically occurs when the vehicle is under maximum throttle and about to shift gears, resulting in a hesitation and a backfiring sound.

Faulty coil packs, worn spark plugs, or malfunctioning vacuum pump valves can contribute to this problem. For example, the 2020 C43 with stage 2 tuning has been known to exhibit misfires when pushed to the limit. Vehicle owners who experience similar issues should have their vehicle inspected to identify the root cause.

Checking the coil packs, spark plugs, and vacuum pump valve can help determine the source of the problem. In some cases, a simple repair or replacement can resolve the issue.