1994 3VZE 4runner 226K Miles

Hey there, I'm having issues with an intermittent CEL that started popping up about a week ago about every 3 or 4th time I drive the vehicle. When I perform the CEL light blink number diagnostic, I get Error Code 52 (no signal from Knock Sensor), whether the CEL light was on last drive or not. Performance and gas mileage has definitely gotten worse since this started happening so it seems like the ECU is limiting performance to protect the engine.

About 9 months ago, I had a knowledgeable technician remove the plenum and replace the fuel injectors, and while he was in there he found the knock sensor had been moved to a different location than originally installed. We put in a new OEM knock sensor back in the original location, and installed a new OEM pigtail connector. Hypothetically, this should have kept what is happening now from happening .

I really do not want to have to pull the plenum again unless absolutely necessary, is there any way to test that the knock sensor has continuity with a multimeter or something? Anything else I could check first to be safe? Run new wires from the pigtail to the ECU maybe? I read somewhere replacing the caps on the ECU might be worth looking into. Thanks in advance.

 

IIRC the resistance dips toward zero when theres knocking. Can simulate that by tapping on block nearby with a hammer.
Then you also have the harness where the pigtail connects back to the ecu (?).

Good luck.
Not financial advice.