DO NOT PUT THREAD LOCK ON THE KNOCK SENSOR!!!! Don't put ANYTHING on the thread. There's plently of posts previously about people lubricating bolts first, and then snapping them when they are done up, due to the lube causing a bolt to be done up tighter. All those measurements are for DRY bolts. The bolt will most likely never come undone. Neither will piston slap cause any problems....why? Because *most* cars don't have piston slap at 2500-3000 rpm (when the knock sensor starts to be used)....If you get fine acceleration using low octane fuel in bad weather, then the knock sensor should be perfectly fine. The looser the knock sensor, the more chance of knock (read: Detonation read: conrod out side of engine). the knock sensor activates at higher rpms, not deativates..... Sounds to me like you might have either: a funny o2 sensor, or, a "dirty" signal from the hall sensor, or whatever it is on that model. The units can wear out and as they "die" the computer can get confused trying to define what state the sensor is in........give me an e-mail if you need anything else, hope it helps,
Az