EXHAUST SYSTEM RESTRICTED DIAGNOSIS. Pontiac Parisienne (Canada) 1981

For 1990-2009 cars

# EXHAUST SYSTEM RESTRICTED DIAGNOSIS

OCCASIONALLY, AN OWNER MAY COMMENT OF POOR ENGINE PERFORMANCE OR LACK OF POWER WHEN THE IGNITION AND FUEL SYSTEMS ARE FUNCTIONING NORMALLY. THIS COULD BE CAUSED BY A RESTRICTION IN THE EXHAUST SYSTEM SUCH AS A BENT TAIL PIPE, RESTRICTED CATALYTIC CONVERTER OR OTHER CONDITIONS WHICH CANNOT BE DETECTED BY A VISUAL INSPECTION. A SIMPLE METHOD TO DETERMINE IF THE EXHAUST SYSTEM IS RESTRICTED IS THROUGH THE USE OF A VACUUM GAGE. WITH THE ENGINE AT OPERATING TEMPERATURE, CONNECT THE VACUUM GAGE TO ANY CONVENIENT VACUUM PORT ON THE INTAKE MANIFOLD. RUN THE ENGINE AT 1000 RPM AND RECORD THE VACUUM READING. INCREASE RPM SLOWLY TO 2500. OBSERVE THE VACUUM GAGE WHILE HOLDING THE THROTTLE STEADY AT 2500 RPM. IF VACUUM HAS DROPPED, THE EXHAUST SYSTEM SHOULD BE INSPECTED FOR RESTRICTIONS.

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