1. 
   • Inspect at regular intervals
   • Maintains optimal engine performance
2. 
   • Abnormal engine idle
   • Difficult cold start up
   • Abnormal visible exhaust emissions
   • Evidence of compression leakage around porcelain insulator
   • Reduced road performance
   • Reduced fuel economy
3. 
   • At specified intervals as outlined in the Customer Information & Maintenance Booklet
   • Engine miss fire
   • Abnormal engine operating temperature
   • Increased visible exhaust emissions

   !Hint: Always use the correct heat range and grade of spark plug as specified by Nissan. With an appointment, your Nissan dealer can arrange to replace spark plugs with specified replacements in around 1 hour for 4 cylinder engines, and 2 hours for 6 cylinder engines*.

   *Excludes some private import vehicles. Not all models stocked - Special order maybe required on some replacement parts.

WARNING. When performing any checks or maintenance work, closely observe the Maintenance precautions in the Maintenance and do-it-yourself section of your Owners Manual. If in doubt about any checks, have it done by a NISSAN dealer.