SMU - SECTION 6E2 - C7 - DRIVEABILITY & EMISSIONS

SUBJECT: SERVICE MANUAL UPDATE - SECTION 6E2-C7 - DRIVEABILITY AND EMISSIONS - EXHAUST GAS RECIRCULATION (EGR) PRESSURE TRANSDUCER (MODULATOR) CHECK

MODELS: 1989-1994 GEO METRO WITH 1.0L ENGINE (VIN 6)

THE FOLLOWING PROCEDURE REPLACES THE ONE ORIGINALLY PUBLISHED IN THE SERVICE MANUAL.

EXHAUST GAS RECIRCULATION (EGR) PRESSURE TRANSDUCER (MODULATOR) CHECK

1. REMOVE THREE VACUUM HOSES FROM THE EXHAUST GAS RECIRCULATION (EGR) PRESSURE TRANSDUCER (MODULATOR).

2. PLACE FINGER OVER EGR PRESSURE TRANSDUCER TUBE AND BLOW INTO OPPOSITE TUBE, SEE FIGURE 1 (PICTURE IN SERVICE MANUAL DID NOT CHANGE). AIR SHOULD PASS THROUGH FILTER PART OF PRESSURE TRANSDUCER.

3. CONNECT VACUUM PUMP TO TUBE "P" AND PLUG TUBE "Q" WITH YOUR FINGER, SEE FIGURE 2 (PICTURE IN SERVICE MANUAL DID NOT CHANGE).

4. BLOW AIR INTO TUBE "A" WHILE APPLYING VACUUM TO TUBE "P" AT THE SAME TIME. YOU SHOULD BE ABLE TO OBTAIN VACUUM ON THE VACUUM PUMP GAGE.

5. STOP BLOWING AIR INTO TUBE "A" AND VACUUM PUMP GAGE SHOULD INDICATE ZERO.

IF EGR PRESSURE TRANSDUCER FAILS EITHER TEST, REPLACE THE EGR PRESSURE TRANSDUCER.

FIGURES: 02 ATTACHMENTS: 00

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