Installation Procedure

NOTE: Use only the spark plugs specified for use in the vehicle. Do not install spark plugs that are either hotter or colder than those specified for the vehicle. Installing spark plugs of another type can severely damage the engine.

NOTE: Check the gap of all new and reconditioned spark plugs before installation. The pre-set gaps may have changed during handling. Use a round feeler gage to ensure an accurate check. Installing the spark plugs with the wrong gap can cause poor engine performance and may even damage the engine.

Measure the spark plug gap on the spark plugs to be installed. Compare the measurement to the gap specifications. Refer to Ignition System Specifications , correct as necessary.

Fig 1: Locating Spark Plugs

Courtesy of GENERAL MOTORS CORP.

NOTE: Be sure that the spark plug threads smoothly into the cylinder head and the spark plug is fully seated. Use a thread chaser, if necessary, to clean threads in the cylinder head. Cross-threading or failing to fully seat the spark plug can cause overheating of the plug, exhaust blow-by, or thread damage.

NOTE: Refer to Component Fastener Tightening Notice in Cautions and Notices.

Install the spark plugs to the cylinder heads.
Tighten: Tighten the spark plugs to 20 N.m (15 lb ft).
Install the ignition control modules. Refer to Ignition Control Module Replacement - Bank 1 and Ignition Control Module Replacement - Bank 2 .