With the engine in the car how do you access the knock sensor?

From the top?
From underneath?
From the front?

And also does anyone know what size socket it is?

 

Its a 23mm! I replaced it from bottom! Its a pain.

Well, mine was 24mm. YMMV. Aus

 

Thanks, needed that.

What the hell did you get in there from the bottom?

I now have my alternator and battery (RHD) removed but the biggest socket I have is 22mm. Damn!

 

Its a nightmare! U can remove the intake if u have to but its really a tight fit.

 

try a 1" tube spanner. They type they sell to change tap washers may do. It will be loose but should have enough engagement to remove it.

 

I'm gunna pick up a 23mm socket tomorrow.

I have the battery out (RHD), the fuel rail and injectors off and the hose below the intake manifold pulled out of the way.

With the right sized socket I should be good to go.

 

A few people have posted the size as 24mm and 25mm in other threads so keep the receipt for the socket.

 

I figured I'd play it safe and add a 23, 24, and 25mm socket to my collection. Bunnings only had 23 and 25 so I bought both.

Turns out it's a 24.

 

24mm is the one.. You'll need a deep socket. I reach it from the top under the manifold.

 

Boo to people who post before they know. Sorry that you got bum info to start. It is a PITA. It's kind of a blind access. Good luck!