Royal Purple Max-Clean Fuel System Cleaner and Stabilizer

Max-Clean uses polyetheramine (PEA) chemistry confirmed by the brand's TDS, dosed one bottle per tank. PEA is the most-studied class for intake valve deposit removal and injector cleaning. Royal Purple targets GDI engines but TDS confirms compatibility with port injection, carbureted, 2-cycle, and 4-cycle engines on gasoline and diesel. Community signal: 3,045 Amazon ratings at 4.7/5, though less depth than the category benchmark. No independent SAE paper or dyno test found; brand cites a sponsored track test only.

Best for GDI owners running non-Top Tier gasoline who want a PEA-class treatment or mild deposit cleanup. Skip it with consistent Top Tier use — the OEM detergent package covers this. Skip it for severe rough idle or stalling; a single consumer bottle is not enough — professional ultrasonic cleaning is the right call.

SDS §2 is DANGER — H304 only (aspiration toxicant: swallowed liquid entering the lungs — not contact or inhalation). No skin, eye, or respiratory H-codes at mixture level. Do not induce vomiting if ingested — seek medical attention. The Amazon listing carries a Prop 65 warning; SDS §15 names cumene as the carcinogen. The product enters the fuel tank and combusts — exhaust byproducts are the environmental endpoint.