Spark Plugs

This vehicle should be serviced with one of the following types of iridium tipped spark plugs.
^ Denso Type SK16R11
^ NGK Type IFR5A11
^ Replace the spark plugs every 144,000 km (90,000 miles).
^ Do not touch the tip of the spark plug.
^ Do not damage the iridium surface of the electrode when gapping the plug.
^ Do not adjust the gap on used spark plugs. Replace the spark plug if the gap is greater than specification.
^ Bend only the side electrode when gapping the spark plugs.

New Spark Plug Gap
1.0-1.1 mm (0.040-0.043 in)

Maximum Used Spark Plug Gap
1.2 mm (0.047 in)

Normal service is assumed to be a mixture of idling, slow-speed and high-speed driving. Occasional or intermittent highway driving is needed for good spark plug performance. The higher combustion temperatures generated during highway driving burn away carbon and oxide deposits that have built up from frequent idling or continuous stop and go driving.

Spark plugs must operate within certain temperature limits to provide the performance and service life expected. The spark plugs selected for an engine is based only on normal engine service, and may not apply for abnormal engine service conditions. For instance, a spark plug one step hotter in heat range might deliver longer service life than the spark plug recommended for almost exclusive city driving. Conversely, a spark plug one step colder than recommended will perform better for continuous high speed driving.

There are three rules to follow when selecting spark plugs for an engine in good condition:
1. Select a spark plug with the specified heat range.
2. Should spark plug overheating occur, select a spark plug one step colder than the specified heat range.
3. If fouling is a problem, select a spark plug one step hotter than the specified heat range.