Driving on the highway when my RPMs suddenly jumped as if the transmission wasn't shifting gears and heard a single loud pop before sudden loss of power and power steering. All electrical accessories continued to run but the engine stalled. When I attempted to start it again, the crank sounded strained or "whiny" and it would not start. Used my OBD2 and the only code it revealed was P0330 - Knock Sensor 2 Circuit, Bank 2. Looking at the freeze frame data, the RPMs were at nearly 6000 before it stalled but, from what I could tell at least, everything else seemed normal. I checked the battery with a multimeter and it was at 12.44V. I checked the resistance on the starter relay and it was at .94. The starter was receiving voltage at 12.67 from the battery and between 9-10 from relay. I wanted to rule out a problem here even though it wouldn't have caused an engine stall. I'm looking for ideas on where to look next. It seems unlikely that a faulty knock sensor would cause a stall no start.

The motor has a tick now like a lifter or valve after overheating repair. It seems more sluggish than before especially going into 2 gear. When it was overheated the gauge went all the way hot and then went to cold as it was hot? Replaced water pump, thermostat, clutch fan, clutch, and radiator cap. It is runnning cool but at higher speeds the gauge sometimes goes over the middle line on gauge, sometimes up to 3/4, but doesnt go all the way hot and as slow down it goes back right below middle gauge?