Operation CHARM: Car repair manuals for everyone.

Spark Plug: Description and Operation




1. Spark plugs must fire properly to assure proper engine performance and emission-control. They should operate satisfactorily in normal vehicle service for the specified maintenance interval or they should be replaced.
2. The new plugs should be checked for the proper gap.

Standard value: Plug gap 1.0 - 1.1 mm (0.039 - 0.043 in.)