Idle Speed: Adjustments

Fig. 1, Idle Speed Setting Procedures:

It is very unlikely that this adjustment will be necessary unless the throttle body has been tampered with after production. If high idle speed is a complaint, the most likely cause will be a vacuum leak. A stalling complaint is even less likely to be caused by incorrect throttle plate stop screw position. All trouble codes should first be checked before adjusting the throttle plate stop screw.

ADJUSTMENT PROCEDURES:
Refer to Fig. 1.
1. Unplug spout line and verify that ignition timing is Base + 2 degrees BTDC.
2. Remove PCV hose at the PCV valve and install .200 inch diameter orifice.
3. Disconnect Idle Speed Control-Air Bypass Solenoid.
4. Start engine and run at 2500 rpm for 30 seconds.
5. Place automatic transmission in DRIVE, or manual transmission in NEUTRAL.
6. Check/adjust idle rpm. Turn the throttle plate stop screw to:
a. With Automatic Transaxle 975 - 1075 rpm.
b. With Manual Transaxle 1500 - 1600 rpm.
7. With engine OFF reconnect spout line.
8. Remove orifice from PCV hose and reconnect to PCV valve.
9. With engine OFF reconnect idle speed control-air bypass solenoid verify the throttle is not stuck in the bore and linkage not preventing throttle from closing.
10. Repeat steps 4 and 5 and check curb idle speed.