How to Adjust the Timing in a Pontiac Grand Prix
- 1). Turn off any accessories such as the radio, climate controls and lights. With the engine turned off, locate the crankshaft pulley at the bottom front of the engine and remove and dirt or grime to expose the timing marks.
- 2). Start the engine, allowing it to reach normal operating temperature. Place the transmission in neutral and hold the throttle at 2,000 RPM for 2 minutes. Let the engine idle normally for one minute then rev the engine three times for 1 second each and turn the engine off.
- 3). Attach the timing light to the battery if necessary and then to the number one ignition wire found at the front passenger side of the engine on a six cylinder or the first wire on the passenger side of a four cylinder. Start the engine and allow it to idle for 2 minutes.
- 4). Point the timing light at the crankshaft pulley to determine the amount of adjustment needed. Loosen the distributor mounting bolts and turn the distributor slowly until the pulley timing marks line up with the middle line on the timing light.
- 5). Tighten the distributor mounting bolts and recheck the timing to ensure the distributor didn't move during tightening. Turn off the engine and remove the timing light. Push the number one ignition wire back into place.
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