Is a pressure washer safe for car paint and ceramic coatings?

Yes, when used at sensible automotive pressures, at an appropriate distance and with a wide fan pattern. Avoid concentrating a narrow high-pressure jet on damaged paint, loose trim, badges, seals, panel edges or chipped areas, and do not spray directly into film or wrap edges. Ceramic coatings themselves are generally not harmed by normal pressure washing.

References
  1. Pressure Washer (Glossary of Detailing Terms), International Detailing Association (IDA)
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