I just took the OEM number of the spark plug from the owner's manual and off the original spark plug and cross referenced it to a NGK Iridium plug form their website to match it for an equivalent plug. I then installed it and it works great. If you need the part number I can get it to you. This is from the NGK website for the spark plug I used : Laser Iridium® spark plugs provide superior ignitability and long service life. Smallest tip diameter available Iridium / Platinum surfaces ensure slow wear rate providing stable idle, superior anti fouling, improved fuel efficiency and lower emissions
Laser welded Iridium center electrode tip
Platinum disc welded to backside of ground electrode provides long life
Trivalent Metal Plating for superior anti-corrosion and anti-seizing
Faster starts and quicker acceleration
Better fuel economy and lower emissions
Best OEM Iridium spark plug available
Original Equipment Manufacturer approved design