Engine Controls - Adjustments: Other Geo Metro I

ENGINE MECHANICAL

Note. Unless otherwise indicated, references to Metro also includes Metro LSi & Metro XFi, respectively.

Before performing any on-vehicle adjustments to fuel or ignition systems, ensure engine mechanical condition is okay.

VALVE CLEARANCE

Note. Hydraulic lash adjusters are used. No adjustment is required. Clearance is automatically adjusted by hydraulic lash adjuster.

IGNITION TIMING

IGNITION TIMING SPECIFICATIONS (Degrees BTDC @ RPM) (1)

1. Start engine, and warm it to normal operating temperature. Turn engine off but keep ignition on for 5 seconds. Restart engine, and raise engine speed to 2000 RPM for 5 minutes. Return to idle. Ensure all accessories are off and idle speed is within specification. Adjust idle speed first if it is not within specification. See «IDLE SPEED»(ref-19462-S11750104542001010200000) under IDLE SPEED & MIXTURE.
2. Connect timing light to No. 1 spark plug wire. Remove cap from duty check Data Link Connector (DLC), located in rear corner of engine compartment near left strut tower. Connect a jumper wire between terminals "D" (Black wire) and "E" (Purple/Green wire) of duty check DLC. (Scheme 3)
3. Check timing mark alignment on crankshaft pulley with timing marks on timing belt cover. Ignition timing must be within specification. See «IGNITION TIMING SPECIFICATIONS»(ref-19462-S29423824522001010200000) table.
4. If ignition timing is not as specified, loosen distributor hold-down flange bolts, and rotate distributor to obtain correct ignition timing. Tighten distributor hold-down flange bolts to 11 ft. lbs. (15 N.m). Recheck ignition timing.
5. Turn engine off. Remove jumper wire, and install cap on duty check DLC. Remove test equipment.

Scheme 3

IDLE SPEED & MIXTURE

Note. Air/fuel mixture is controlled by the Engine Control Module (ECM)/Powertrain Control Module (PCM) and is not adjustable.

IDLE SPEED

1. Place transaxle in Park (A/T) or Neutral (M/T), and apply parking brake. Ensure throttle cable has at least.12-.20" (3.1-5.1 mm) of slack in cable. Adjust throttle cable slack (if necessary).
2. Ensure all emission hoses and air cleaner are properly installed. Ensure ignition timing is within specification. See «IGNITION TIMING»(ref-19462-S20218964922001010200000). Ensure all accessories are off. Start engine and warm to normal operating temperature. Connect scan tester to Data Link Connector (DLC). Ensure idle speed is within specification. See the «IDLE SPEED SPECIFICATIONS»(ref-19462-S39838548312001010200000) table.
3. If idle speed requires adjustment, remove cover from idle speed adjusting screw. Turn idle speed adjusting screw inward to increase idle speed or outward to decrease idle speed. (Scheme 4)
4. On A/C-equipped models, turn A/C to low speed. With A/C operating, idle speed should be within specification. See «A/C IDLE SPEED SPECIFICATIONS»(ref-19462-S02305465682001010200000) table.
5. If idle speed requires adjustment, rotate adjustment screw on A/C Vacuum Switching Valve (VSV) to obtain correct idle speed. (Scheme 4) A/C VSV is mounted on firewall, right of ignition coil.
6. Turn engine off. Install idle speed adjusting screw cover (if removed), and remove scan tester.

Scheme 4

IDLE SPEED SPECIFICATIONS (1)

A/C IDLE SPEED SPECIFICATIONS