Originally Posted by tomfurie

i am having the same spark knock issue on my 2006 xkr with 105,000 miles, but only after it gets to operating temperature.
• no codes. (i will check my fuel trims this weekend)
• i run only 93 octane & have run fuel cleaner and octane boos. No effect.
• in the last 2 weeks i have changed all coil packs & spark plugs and have had a full fluid service.
I have searched the download section of this forum as well as the internet and i cannot locate tsb 303-69 for the xkr. If someone has a link, please share.