Base Timing Adjustment

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The ignition timing is controlled by the ECU and may be functioning normally and still adjust depending on the condition of the engine. (i.e. the ECU will change timing if the knock sensor detects "knock"). This procedure will assume that you know how to set-up and use a timing light. Tools needed for changing base timing:

	Timing light
	Jumper wire about 1 foot in length with aligator clips on both ends.

Have the engine in these conditions before staring procedure:

	Engine coolant temperature: 185-205^oF (normal operating temp)
	All electrical accessories turned off.
	Steering wheel in the neutral position
	Transmission is neutral

The adjustment procedure is as follows:

With car running check curb idle speed. Should be 750 (+/- 100) RPM. If idle speed is outside this range adjust curb idle speed to the correct speed first.
With the engine stopped, connect a jumper wire to the terminal for ignition-timing adjustment (located in the engine compartment), and ground it. See illustration.
Start and run the car at curb idle speed.
Check basic ignition timing (5^o BTDC) and adjust if necessary. Timing marks are on the crackshaft pulley on drivers side on engine compartment. See illustration.
If not within the standard value, loosen the crank angle sensor mounting nut and adjust by turning the crack angle sensor. Turning it to the right advances timing, and to the left reetards it. See illustration.
Tighten the nut after adjustment, being sure that it does not move while tightening.
Stop the engine, and remove jumper wire in step 2.
Start the engine again and check the timing again. The correct basic ignition timing with no jumper wire is 8^o BTDC.

Note: actual ignition timing may very, depending on the control mode of the engine control unit. In such a case, re-check the basic ignition timing (without jumper). If there is no deviation, the ignition timing is functioning normally. Also, at high altitudes (2300+ ft.) actual ignition timing is further advanced to ensure good combustion.

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