Idle Speed Adjustments

Fuel Injected
1982-86 2.0L (122): Gain access to throttle stop screw. With engine at operating temperature, disconnect idle air controller and install special tool to seal idle air passage of throttle body. Turn throttle stop screw to specified minimum speed value.

1985-87 2.8L (173) Fuel Injected, 1987 2.0L (122): Ground diagnostic lead and turn ignition on for 30 seconds. Remove IAC electrical lead and remove ground from diagnostic connector. Start engine and set minimum speed to specified value.

1982-85 4.1L (250) and 6.0L (368): Retract ISC plunger by hand and disconnect ISC connector. Set minimum speed to specified value. Check TPS voltage for recommended setting. 6.0L (368) only: disconnect TPS connector and open throttle by hand to approximately 1500 rpm. Close throttle and turn ignition off. ISC plunger should extend fully. Disconnect ISC and start engine. Set maximum speed to specified value.

1986-89 4.1L (250), 4.5L (279) TBI: With engine at operating temperature, turn engine off and disconnect harness from ISC. Apply 12 volts (+) to third terminal from top of ISC (C), and ground the fourth terminal from top (D) only long enough to retract ISC plunger. Start engine and check minimum speed against specified checking valve. If not, set minimum idle to specified value by adjusting base screw.

1987-90 4.1L, 4.5L MFI, 5.7L: With ISC fully retracted, idle should be at specified checking value.