My knock sensor has always given me problems. I have rewired it twice, and I am very confident that the wiring is sound. Every connection is soldered and I used a pin to the correct slot on the p13 ECU. About every week or two, I get the CEL. I reset the ECU, and I may go two days or three weeks and the CEL comes back. I've removed the Knock Sensor, cleaned the contact, and put it back. There is nothing to service on the knock sensor. How do I test it? Is there a way to fool the computer so that I can make 100 percent sure it is not the ECU or my wiring? Any other options? I don't mind replacing the sensor with a new one, I'm not cheap. However, I don't want to spend $140 on a sensor that I don't need. Any and all suggestions appreciated. Oh, one other thing. When I get the CEL, it is usually while just cruising or lightly accelerating @ ~3000 rpms. I double checked the timing myself and it's fine.