Regal V6-191 3.1L (1991)
Idle Speed: Adjustments
Idle Speed
Fuel Injection
Stop Screw Plug Removal
NOTE: The throttle stop screw, which controls minimum idle speed, is adjusted at the factory and covered with a plug to discourage unnecessary
adjustment. Normally, it should not be necessary to adjust unless the throttle body is replaced.
To gain access to the throttle stop screw, pierce the plug with an awl, and apply leverage as illustrated to remove the plug.
ADJUSTMENT:
NOTE: Tool Required: TECH 1 Scan tool or equivalent.
1.
Back idle stop screw out until there is an air gap between the screw and the throttle lever.
2.
Turn the screw in until it just touches the throttle lever.
3.
Turn the screw in an additional 1 1/2 turns.
4.
Refer to IDLE LEARN PROCEDURE. The ECM will need to relearn the IAC valve position if the battery was disconnected.
5.
Connect a scan tool to the ALDL connector.
6.
Place transmission in "PARK" (A/T) or "Neutral" (MAN).
7.
START engine and allow it to reach normal operating temperature about 90~C (194~F) and "Closed Loop".
8.
Observe Idle Air Control (IAC) counts displayed on the "Scan" tool.
9.
With the engine stabilized, IAC valve position should be 10-20 counts. If not repeat procedure. Observe "counts" on scan tool with all accessories
"OFF" and the transmission in PARK or NEUTRAL. Also make sure the engine cooling fan is "OFF." Also make sure the throttle and cruise
control cables do not hold open throttle valve.
Idle Learn Procedure
Anytime the battery is disconnected, the programmed position of the IAC valve is lost and is replaced with a default value. To restore the idle air control
valve position information, perform the following procedure:
NOTE: The following procedure applies only to the TECH 1 Scan tool.
Consult the owners manual of the Scan tool being used for specific instructions on how to perform the "IDLE LEARN" procedure.
1.
Install Tech 1 Scan tool or equivalent.
2.
Ignition "ON," and engine "OFF."
3.
Shift transaxil to PARK (A/T), NEUTRAL (M/T).
4.
Select "IAC SYSTEM," then "IDLE LEARN" in the "MISC TEST" mode.
5.
Proceed with idle learn as directed.
