SMU-SECTION 6E2-SUPPLEMENTAL IDLE SPEED ADJUSTMENT

SUBJECT: SERVICE MANUAL UPDATE-SECTION 6E2-SUPPLEMENTAL IDLE SPEED ADJUSTMENT

MODELS: 1991-93 GEO METRO 1994 GEO METRO - "STANDAND EMISSIONS" ONLY WITH 1.0L ENIGNE (VIN 6 - RPO LP2)

THIS BULLETIN PROVIDES A SUPPLEMENTARY PROCEDURE TO THE IDLE SPEED ADJUSTMENT.

IF THE IDLE SPEED CAN NOT BE BROUGHT INTO SPECIFICATION (IDLE SPEED TOO HIGH) WHEN FOLLOWING THE PROCEDURES FOUND IN THE FOLLOWING SERVICE MANUALS.

PROCEDURE:

* "IDLE SPEED ADJUSTMENT-STANDARD EMISSIONS," 1994 METRO SECTION 6E2-C2-11 1.0L (VIN 6).

* "IDLE SPEED ADJUSTMENT," 1993 METRO SECTION 6E2-C2-9 1.0L (VIN 6).

* "IDLE ADJUSTMENT," 1991-1992 METRO SECTION 6E2-C2-8 1.0L (VIN 6).

A. WITH ENGINE IDLING AT NORMAL OPERATING TEMPERATURE, DISCONNECT IAC VALVE CONNECTOR. B. REMOVE CAP FROM THROTTLE STOP SCREW. (FIGURE 1). C. LOOSEN THE THROTTLE STOP SCREW LOCK NUT. D. ADJUST THE THROTTLE STOP SCREW USING THE FOLLOWING SPECIFICATIONS:

*1991-1994 1/8 TURN (CCW) COUNTER CLOCKWISE WITH MANUAL TRANSAXLES. *1991-1994 1/4 TURN FOR AUTOMATIC TRANSAXLES.

NOTICE: SPECIAL CARE MUST BE TAKEN NOT TO SCORE THE MAIN BORE WITH THE THROTTLE VALVE EDGE IF IT IS ADJUSTED EXCEEDING THE RECOMMENDED CRITERIA.

E. IS IDLE WITHIN SPECIFICATIONS? IF NOT, ADJUST ACCORDINGLY. F. TIGHTEN THE LOCK NUT TO THE SPECIFIED TORQUE VALVE, INSTALL THE CAP BACK ON THE THROTTLE STOP SCREW.

TIGHTEN* *THROTTLE STOP LOCK-NUT TO 2.8-4.0 N.M (25-35 LBS. IN.).

G. CHECK AND OR ADJUST TP SENSOR IF NOT WITHIN SPECIFICATIONS, FOLLOWING THE SERVICE MANUAL PROCEDURES. H. CONNECT THE IDLE AIR CONTROL (IAC) VALVE CONNECTOR.

IMPORTANT: AFTER PERFORMING THIS ADJUSTMENT, IAC/ISC DUTY MAY APPEAR OUT OF SPECIFIED RANGE. IF THIS OCCURS, DISREGARD IAC/ISC DUTY. IT IS MORE IMPORTANT THAT IDLE SPEED IS IN PROPER RANGE.

FIGURES: 1 ATTACHMENTS: 00

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