Engine - Hard Throttle Misfire

87pontiac08

Number 87-6(Gasoline)-53 Date 9/87


Subject: ENGINE MISFIRE UNDER HARD THROTTLE, I.E.., TURBO BOOST


1987 2.0L LT3 (VIN CODE M) ENGINE
Some engines may misfire under hard throttle, such as during turbo boost conditions. The miss is caused by excessively high ignition system demand voltage of the high gap (.060") spark plug and combustion conditions.

The misfire is repairable by installing a .035" gap spark plug with service P/N 5613820 (R42XLS, a previous 1986 turbo spark plug).

For future spark plug service on this vehicle, non-destructible peeloff labels are included with this bulletin. This reference label should be placed on the same mounting surface as the current vehicle emission control information, "Tune-Up" label.

Use applicable labor operations and labor time.