Postby smj999smj » Wed Dec 18, 2013 5:36 pm
I wonder if a cam sensor might be starting to "go south." It shouldn't ping on 93 octane. Timing is controlled by the computer, so there's no manual adjustment that could be off. Excessive carbon on the piston tops can increase compression and cause pinging, but I've yet to see that on a VQ engine. I would agree with the other poster and try getting your fuel from another source and see what happens.