Misses Under Load

Definition: Steady pulsation or jerking that follows engine speed, usually more pronounced as engine load increases. The exhaust has a steady spitting sound at idle or low speed.

POSSIBLE CAUSE ACTION

Contaminated fuel [1] Drain fuel tank and add clean gasoline

Restricted fuel filter/line Replace filter/repair restricted line

Incorrect fuel pressure See FUEL PUMP AND PRESSURE REGULATOR (SYSTEM PRESSURE CHECKS) under COMPONENT TESTING

Plugged fuel injector(s) - Poor injector spray pattern See FUEL INJECTORS under COMPONENT TESTING



[1] Mazda reccommends the use of UNLEADED REGULAR gasoline only, in all vehicles not equipped with a turbocharger. Do not use, or reccommend for use, any higher octane fuels. Starting, idle, and driveability problems may result. See factory Technical Service Bullitin #054/89, titled "USE OF REGULAR UNLEADED GASOLINE".