ASPIRATOR SYSTEM OP TEST INFORMATION. Pontiac Parisienne (Canada) 1981

For 1990-2009 cars

# ASPIRATOR SYSTEM OP TEST INFORMATION

ASPIRATOR PART NUMBER 25030978, USED IN 1981 "B" 3.8L (LD5) AIR CLEANER ASSEMBLY NUMBER 25040815, PROVIDES A VACUUM SIGNAL TO THE EGR VALVE BY USING THE DIVERT AIR FROM THE A.I.R. CONTROL VALVE UNDER LOW ENGINE VACUUM CONDITIONS. THE ASPIRATOR CONTAINS A BACK PRESSURE VALVE WHICH CREATES SUFFICIENT BACK PRESSURE TO OPERATE AN INTERNAL VENTURI SYSTEM THAT CREATES THE VACUUM SIGNAL. DIVERT AIR ENTERING PART "A" (SEE ILLUSTRATION OF PAGE 2 OF THIS BULLETIN) IS RESTRICTED FROM DISCHARGING INTO THE AIR CLEANER BY THE VALVE AND SPRING IN THE ASPIRATOR. THE PRESSURE DEVELOPED IN THE LINE FEEDING PORT "A" ALSO FLOWS THROUGH A VENTURI SYSTEM WITHIN THE ASPIRATOR, WHEN PORT "C" IS OPEN, CREATING A VACUUM AT PORT "B". TO PERFORM A BASIC FUNCTIONAL CHECK ON THE ASPIRATOR ASSEMBLY: 1.DISCONNECT HOSE FROM PORT "C" AND TEMPORARILY PLUG HOSE (LEAVE PORT "C" OPEN TO ATMOSPHERE). 2.ATTACH A VACUUM GAGE TO PORT "B". 3.RUN ENGINE UNTIL A.I.R. VALVE DIVERTS AIR TO THE AIR CLEANER (THIS AIR FLOW CAN BE FELT AT THE ASPIRATOR OUTLET INSIDE AIR CLEANER. 4.WHILE RUNNING ENGINE AT 1500 RPM (IN PARK) VACUUM GAGE SHOULD READ GREATER THAN 3 INCHES HG. IF ASPIRATOR WILL NOT DEVELOP GREATER THAN 3 INCHES HG, CHECK FOR SPLIT OR DAMAGED AIR LINES. IF NO LEAKS ARE FOUND, INSTALL NEW ASPIRATOR ASSEMBLY AND REPEAT ABOVE PROCEDURE. IF NEW ASPIRATOR WILL NOT DEVELOP GREATER THAN 3 INCHES HG, CHECK FOR MALFUNCTIONING A.I.R. VALVE OR A.I.R. PUMP.

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