P0325 >:(!
 

I bought this EK with a CEL, and diagnosed that it was a P0325, so I changed the knock sensor in it and it was okay....for 2 months/6000kms. Then the CEL came on again, so I went to check it....P0325, Pre detonation...although it did just cross over into winter...So, I took the plugs out and they were pretty done, I replaced those and put in 91 octane gas to help compensate for the denser air. It worked for about two hours but then the light came on again. I don't notice any pinging or knocking but I'm ready to throw this car in the trash :( Any suggestions for clearing this CEL? It shouldn't have burned through another knock sensor should it?