Ranger 2WD V6-171 2.8L (1983)
Idle Speed: Adjustments
V6-171 Engine
If curb idle speed is not correct after performing the following procedure, the appropriate EEC-IV system diagnosis will have to be performed.
1.
Start engine and allow to reach normal operating temperature in Park, if automatic transmission, or Neutral, if manual transmission. Set parking
brake and block wheels, and turn off all accessories.
2.
Remove air charge temperature sensor and adapter from air cleaner, leaving it connected to wiring harness. Remove air cleaner, disconnect and
plug vacuum line at bottom of air cleaner.
3.
Shut engine off, and check that idle speed control plunger moves out to maximum extension within 10 seconds.
4.
Disconnect idle speed control. Disconnect and plug EGR vacuum line.
5.
Start engine, open throttle and position fast idle adjusting screw on highest step of cam.
6.
Adjust fast idle speed to specification.
7.
Open throttle manually to release fast idle cam and allow throttle lever to rest on idle speed control plunger.
8.
Loosen idle speed control bracket lock screw. Adjust bracket screw to 2000 RPM and retighten.
9.
Reconnect idle speed control and check that engine speed is automatically adjusted to curb idle.
10.
Hold throttle above 1000 RPM and push idle speed control plunger until it retracts fully. When plunger has retracted, release throttle and quickly
unplug connector.
11.
Adjust anti-dieseling speed throttle stop screw to 750 RPM in Neutral for 1983 - 84 vehicles with manual transmissions and all 1985 - 86 vehicles,
or to 650 RPM in Drive for 1983 - 84 vehicles with automatic transmissions. If throttle stop screw is not slotted and adjustment is required, grasp
screw threads with pliers and turn screw to remove. Install new throttle stop screw and adjust to specification.
12.
Reconnect idle speed control connector and EGR vacuum line.
13.
Shut engine off.
14.
Restart engine and check that curb idle speed is correct.
