Repair 7

90 Geo Prizm Timing Specs

Correct ignition timing specifications are crucial for engine performance. Timing affects many variables, including fuel economy and engine longevity. Prizm is a compact car manufactured in United States by Chevrolet since1989. Its engineers have determined precise timing specifications so that you can benefit from your Prizm as much as possible.

Measuring Ignition Timing

Use a timing light to check your timing while the engine is running. An inductive trigger signal will be picked up from one of the spark plug cables, causing the light to turn on and freeze while the spark plug fires. This helps to determine the crankshaft position. Use this information for making timing adjustments, because the rate at which the crankshaft is spinning and is processed by the distributor controls the ignition (that is, controls when the spark should occur).

Timing Specifications

Ideally, the time at which the mixture should be fully burned on a Geo Prizm is approximately 10 degrees before top dead center (BTDC) at idle.

Notes

These adjustment specifications are both for automatic and manual transmission versions.