Fuel - Engine Stall or Rough Idle When Cold

89mazda08

Category 4
Applicable Model/s 1988-1989 929
Subject ROUGH IDLE OR ENGINE STALL WHEN ENGINE IS COLD
Bulletin No. 063/89
Issued 11/8/89
Revised
DESCRIPTION

Engine speed drops excessively and occasionally stalls when shifted into "D" or "R" just after starting a cold engine. This problem is likely to occur if premium gasoline is used especially when the ambient temperature is around 20~C (68~F).

Due to low volatility of some premium gasolines, an overlean air fuel condition may occur. This may result in rough idle or a stall problem just after cold start.


REPAIR PROCEDURE

1. Instruct the customers to use regular unleaded gasoline instead of using premium as described in our previous Service Bulletin, Category 4, 054/89.

2. If the problem is not solved by the above measure, replace the E.C.U. with a modified one which will provide a controlled and enriched air-fuel condition after starting when the ambient temperature is around 200C (68~F).


PARTS INFORMATION


REBUILT E.C.U. REGULAR E.C.U. INTERCHANGEABILITY APPLIED MODEL

JEY6 18 881R JE06 18 880G NEW FITS OLD Federal Spec.

JEY7 18 881R JE07 18 880C NEW FITS OLD California Spec.