PRIMARY VACUUM BREAK SETTINGS NON CLOSED LOOP EMISSIONS. Pontiac Parisienne (Canada) 1981

For 1990-2009 cars

# PRIMARY VACUUM BREAK SETTINGS NON CLOSED LOOP EMISSIONS

TO ASSIST IN PROVIDING BETTER ENGINE CHOKE UNLOADING AND MINIMIZE SPARK PLUG FOULING, PRIMARY VACUUM BREAK SETTINGS HAVE BEEN REVISED FROM 18F TO 22F. THIS REVISED SETTING MAY HAVE A TENDENCY TO INCREASE THE PROBABILITY OF A "STALL AFTER START". USE THE FOLLOWING CHART AS AN AID IN DETERMINING THE APPROPRIATE SERVICE ACTION. ORIGINAL V.B. SETTING 18F COMMENT SPARK PLUG "FOULING" LOADING ETC. REVISED V.B. SETTING 22F EXPECTED RESULT IMPROVED LOADING OCCASIONAL "STALL-AFTER-START" ORIGINAL V.B. SETTING 22F COMMENT STALL-AFTER-START REVISED V.B.SETTING 18F EXPECTED RESULT NO STALLS. SOME LOADING DEPENDING ON DRIVING SCHEDULE IN NO CASE SHOULD THE SECONDARY VACUUM BREAK SETTING BE REVISED.

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