2021 BMW M4 Problems & Defect Complaints

Domain Share Note: Share percentage represents the proportion of unique complaint filings referencing each vehicle system. Because single complaints may cite multiple systems (such as engine and electrical simultaneously), domain percentages represent individual category incidence and may sum to over 100%.

Consumer Narrative Notice: Excerpts are sanitized text descriptions submitted by vehicle owners to the federal ODI database. They reflect the reporting consumer's observations at the time of filing and have not been independently confirmed by vehicle manufacturers or government investigators.

Comparative Disclaimer: Complaint totals are unadjusted historical counts and are not normalized for vehicles sold, active fleet size, or total road mileage. Newer model years naturally have had less calendar exposure time to accumulate owner filings.

Data Attribution & Reporting Methodology: Complaints are unverified voluntary submissions to the NHTSA Office of Defects Investigation (ODI). Because multiple vehicle components can be cited within a single owner complaint submission, component-level rollups may sum to more than the unique complaint count (1). Injury and fatality entries in the detailed table reflect raw values entered by reporting consumers across individual submissions; they are not deduplicated casualty statistics and may include duplicate or unverified entries. Complaint volume is not normalized for sales volume or vehicle mileage and does not represent an audited component failure rate.