So I trolled this site looking for help when rebuilding the 3.0 in my 4Runner. So first off thank you for the vacuum line help along with some tips and tricks on previous write-ups. I figured it was only fair I contribute when ran into the Code 52 issue.

The background is I did a complete long block rebuild and replaced the knock sensor with a brand new one from Toyota with the new pig tail. Of course after my initial start up, I start getting the CEL for code 52. The old motor did not throw a code, so I knew the wiring should be good. I did the continuity test at the ECU and it was less than .05 voltage drop. Cleaned the connection points, same thing, traced the wire back, and still no go.

I did everything but replace the wire to the ECU and/or a new knock sensor. Instead of spending 1-2 hours opening back up the intake, this is what I came up with and I'm not sure it's been spoke about anywhere else?

I went and pulled a used knock sensor out of a junk yard 4runner that looked in good shape and most of the top end of the motor was already disassembled. I then drilled and tapped a new hole in the Driver's side engine hoist hook mount. I installed the 'new' knock sensor there, plugged it in, and problem solved! I also grabbed a spare hoist mount off the old motor just in case I ever need to pull the motor again. I'll post up some pics shortly, and you're welcome.

 

good info but has been covered a few times. There is an issue to doing that tho. It wont detect as well as where the original sits but still a much simpler solution.

 

I've searched for a few weeks on different sites and this seems to be a much better option.

 

Clean looking engine from what I can see..nice.