If you experience engine knocking or pinging, or poor fuel mileage, timing is likely the issue. Ignition timing helps the engine receive fuel and air sent by the spark plug at the proper time..
Timing that is early causes the fuel to detonate before it reaches the piston, which wastes fuel, and late timing lowers engine pressure. You can easily adjust engine timing yourself by following these steps.
Prepare to Fix the Timing
You will need a distributor wrench or socket wrench, timing light, and your manual. Park vehicle on a flat surface, and shut off the engine. Activate the parking brake, and prop the hood. Look for the distributor (flywheel), which should be on top of the engine, or refer to your manual.
The distributor will be marked with a line of numbers above and below zero similar to a ruler. The marks show how far the piston is from dead center.
Check the Timing
Attach the timing light or timing gun to the battery ground and terminal cables, then attach the timing light sensor to the first cylinder, referring to your manual for the position. The timing light commonly has a clamp for negative and positive wires and an inductive clamp to hook on the spark plug wire.
The light illuminates the mark on the distributor like a strobe light, while it rotates to highlight the position from where the spark is firing from top dead center. Get an assistant to start the engine, let it get to 195 degrees, and watch to see where the light illuminates. After the spark plug fires, the sensor should send a signal to the timing light.
Observe the number of degrees above or below zero. The position from where the spark plug is firing should increase as the RPMs (Rotations Per Minute) increase. Compare the highlighted position with the suggested point in your manual.
Adjust the Timing
The common top dead center position is ten degrees, but each manufacturer specific the correct position. Let the engine cool, and use an adjustable wrench or socket wrench to turn the distributor until it reaches this position. You may need to loosen the distributor bolt on the rear of the manifold slightly to turn the distributor.
If necessary, detach the vacuum hose, and insert a bolt or a similar object in the hole to prevent leaks. Turning the bolt to the right retards timing, and turning the bolt left advances timing. Reattach the vacuum, tighten the nut, and disengage the parking brake. Have the assistant press the accelerator pedal, then release to get the vehicle back in idle, and confirm the adjustment.
Contact a shop, like Westside Fender/Body & Refinishing, for more help.