405 L4-1905cc 1.9L (1989)
Fig. 10 First Throttle Adjustment
1.
Remove the tamper resistant plug from screw (1), then loosen screw until it no longer touches lever (2), Fig. 10.
2.
Insert a .002 inch (.05mm), feeler gauge between lever (2) and screw (1).
3.
Tighten screw (1), until the slightest pressure is applied to the feeler gauge, without moving lever (2). The feeler gauge must be free to move
between lever and screw, without moving lever.
4.
Remove feeler gauge, tighten screw an additional 1/4 turn, then install a new tamper resistant plug.
Fuel Mixture
The air fuel mixture at idle is not adjustable. It is adapted automatically by the ECU based on input from the Oxygen Sensor. On-Board Diagnostics
continually check the richness adaptation which is done by the ECU. Error code 51 will be set and the "CHECK ENGINE" indicator will illuminate if a
fault with this system is detected.
Idle Speed Adjustment
Be sure the following conditions are met before attempting to adjust the idle.
a. The engine must at normal operating temperature.
b. The ignition system is in good operating condition.
c. The air filter is in good condition and is in place.
d. The cooling fans are off.
e. The A/C compressor is off.
f.
The automatic transmission is in N or P.
g. The engine is in good mechanical operating condition.
1.
Connect a scope or suitable tachometer.
