Rough, Unstable or Incorrect Idle; Stalling

Definition: The engine runs unevenly at idle. If bad enough, the vehicle may shake. Also, the idle may vary in rpm. Either condition may be severe enough to cause stalling. Engine idles at incorrect speed.

POSSIBLE CAUSE ACTION

Poor or contaminated fuel [1] Drain fuel tank and fill with clean gasoline

Incorrect air/fuel ratio Check air/fuel ratio,
Refer to COMPUTERIZED ENGINE CONTROLS

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

Incorrect idle speed Check and adjust
Proceed to ADJUSTMENT PROCEDURES


[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".