Here's a general outline of the procedure, but always defer to your vehicle's repair manual:
1. Safety First: Disconnect the negative battery cable before starting any work on the ignition system.
2. Locate Timing Marks: This is the most critical step. You'll need to find the timing marks on the crankshaft pulley (usually a notch or indicator) and the timing chain cover (usually a series of marks and/or an indicator). Your repair manual will show you exactly where these are located and how to interpret them. They might be accessed by removing a cover or shroud.
3. Access the Distributor (if applicable): Some 2.2L Ecotec engines use a distributor, while others are distributorless. If your engine has a distributor, you'll need to be able to rotate it.
4. Engine Temperature: Ensure the engine is at operating temperature as specified in your repair manual.
5. Connect the Timing Light: Hook up the timing light according to its instructions. The clamp goes around the spark plug wire.
6. Set the Engine to Top Dead Center (TDC): With the ignition OFF, manually rotate the crankshaft until the crankshaft timing mark aligns with the reference mark on the timing chain cover. Double-check your repair manual for the correct alignment. This step is crucial for accuracy.
7. Start the Engine: Have an assistant crank the engine while you aim the timing light at the crankshaft pulley. The timing light will illuminate the timing marks, showing the crankshaft's rotational position.
8. Adjust Timing (if needed): The timing light will show the crankshaft's position relative to the timing marks. Your repair manual will specify the correct timing degree. If the timing is off, you may need to adjust the distributor (if applicable) by loosening its clamp and rotating it slightly. Again, consult your manual for the direction and procedure for adjusting timing. Modern Ecotecs often don't have a distributor.
9. Recheck Timing: After making any adjustments, recheck the timing with the timing light to ensure it's correct.
10. Reconnect Battery: Once the timing is set correctly, reconnect the negative battery cable.
Why you absolutely need a repair manual:
* Specific Timing Marks: The location and interpretation of timing marks vary significantly between years and models.
* Distributor Location and Adjustment: The presence, location, and adjustment procedure of a distributor (if present) are engine-specific.
* Special Tools: Some procedures may require specialized tools.
* Safety Precautions: Repair manuals detail important safety precautions to protect you and your vehicle.
Failing to use a repair manual specific to your 2.2L Ecotec engine could lead to serious damage, including bent valves or other internal engine damage. It's a much safer and more effective way to correctly set your timing.
