I have a 1990 4runner that has a code 52 I have replaced the knock sensor and pigtail wiring harness and have checked the wire from the ecu to the wire harness connector and it all checks good also have checked the timing and it is set at 10btdc but still have the same code! I clear the code and lt comes back when the motor is warm. I'm lost and don't know what else to check and running out of money!!

 

I dont have a code book close, what is 52?

 

code 52 is a knock sensor code