Just a thought....I too have Track Key installed, has been since I purchased it, well the second day they installed it, it had to be shipped. I have never had a issue with knock, pre-detonation or anything like it. I have always used premium fuel which here is 92 or 93, and I buy at Shell (Now Speedway) and BP. Sonoco has 94. In our area, because of EPA constraints, we have what is known as Reformulated gas. This has been known to cause many problems in both cars and lawn type equipment. Not sure what all is in this stuff, but items like a weed whacker, or similar equipment only last a season, then its toast. I have always used quality products like Stilh, but regardless of brand, it does not last. In fact, I stopped buying gas powered lawn equipment, but last time I visited the Stilh dealer, they were selling a special gas in 1 QT and 1 Gal containers just for this reason.. Anyway, I know several communities have this stuff, and it causes problems. We even have travelers and visitors that fill up here and suddenly developed engine trouble. I don't know how it can be so good for the environment when it causes such troubles and decreased mileage? I know when we visit outlying areas and fill-up there, the car runs better, all cars.