I got my 2003 S Type R with about 40,000 miles on it. I was thinking about changing the spark plugs and I took one out and it was a NGK IFR5N10. I read on here that they are good for about 100,000 miles. My car is at 112,000 now and I was wondering if these are the OEM plugs that Jaguar uses on this car or if they were probably changed by the previous owner. Thanks for any help.

 

Change them to the NGK Iridium plugs. You will never have to change them again!

 

I tried to switch to champion plugs, and they did not start as easy in cold weather, even flooded a few times. Went back to NGK and everything works fine.