I have code 52, I understand there is a problem with the circuit. I can see the pigtail is showing raw wire where it's coming out of the intake plenum. I am going to rewire with coax cable from the ecu to the knock sensor. Where do I ground the coax? Or does the coax only connect into the ecu?

 

The knock sensor is grounded ONLY at the ECU end, not at the knock sensor. The lead and the shield go through the EB1 connector (the one near the throttle body), but the shield is not connected at the sensor. The shield is combined with a number of other grounded leads from the ECU, but I wouldn't say that it is connected "into" the ECU.

 

Thanks scope. That makes total sense to me, except for where the shielding should join the other grounds. I'm probably just over looking it...

 

I don't KNOW, but the EWD I have shows all grounds as solid Brown. There a number going to the ECU, so I would expect to find of bunch of Brown wires that all go to a crimp buried inside the harness somewhere. And the shields (knock sensor, O2 sensor, ) would probably go there.

 

When I re-ran shielded wire to my knock sensor, I grounded it on the ECU mounting point.

 

Ok, thanks @128keaton. That's what I will try. I plan on mocking up the wiring inside the cab before I completely take the intake plenum off, so i can work out any kinks. I'll give it a shot this week and report back.