Last winter I install fuel injection from a 90 22re on my 87 22r. When I reach about 2500 rpm's it throws CEL 52. Tried another knock sensor with the same results. Went to a Toyota only wrecking yard and they gave me a knock sensor that is larger in diameter but the connectors are the same. They said it did not matter which sensor I used. I installed the larger sensor and truck runs great. The larger sensor looks like the one in my 3.slow. Does it make a difference if I use the larger knock sensor? Any ideas why the smaller sensor throws the CEL 52.