Hesitates or Stalls on Acceleration

***UPDATED BY TSB #F00991 DATED MARCH 22, 1991

Some 1989-1991 RX7 turbo owners may complain of engine hesitation. This occurs during hard acceleration between 3,500 - 4,000 rpm. There are two possible repair procedures to correct this problem. Refer to factory service bulletin #F00991, titled "HESIATION ON HARD ACCELERATION BETWEEN 3500-4000 RPM".

***UPDATED BY TSB #405489 DATED FEB. 20, 1989

Mazda recommends the use of UNLEADED REGULAR gasoline only, in all vehicles not equipped with a turbocharger, unless otherwise specified. Do not use, or recommend for use, any higher octane fuels. Starting, idle, and driveability problems may result. See factory Technical Service Bulletin #405489, titled "USE OF REGULAR UNLEADED GASOLINE".

Definition: Momentary lack of response as the accelerator is pushed down. Can occur at any vehicle speed. Usually most severe when first trying to make the vehicle move, as from a stop sign. May cause the vehicle to stall if severe enough.

POSSIBLE CAUSE ACTION

Unmeasured air entering intake system (vacuum leak or Repair air leak
air leak between air flow sensor and throttle valve)

Poor or contaminated fuel Drain fuel tank and fill with clean gasoline

Incorrect air/fuel ratio Check fuel pressure.
Also check oxygen sensor and closed loop computer operation.

Plugged fuel injector(s), or Check fuel injectors
poor injector spray pattern