What tool do I need to remove knock sensor?

[KRAM36]

One of the fault code I got was porsche fault code 210 knock sensor 1. So I bought 2 so I would have matching units. Looking at this picture it seems to take a different tool to remove the bolt. Purple arrow is the know sensor. What tool do I need for this?

[steved0x]

I can't see from the picture but maybe a Torx head? Like this?

I just bought this set a month or so ago at Harbor Freight so I could remove my passenger seat.

http://www.harborfreight.com/17-piece-14-in-38-in-drive-star-bit-socket-set-67930.html

[KRAM36]

Excellent, thank you Steve.

Man Porsche sure berried these on the engine. Still waiting on some parts to come in for my throttle body and air box upgrade, plus I'm putting in a new starter. I'll have access to them then.

[BYprodriver]

13mm wrench

[Gelbster]

The fastener head in the photo is an " E " & you need an E socket for it.
My 2001 M96 did not have the E-head fastener.
The instructions for my new knock sensors assumed(?) it was being bolted onto an iron block and the torque spec would have stripped the threads on the M96. Be careful and consider substituting a s/s stud+nut if you want over 10Nm torque.Bee very careful where you apply silicone!

[KRAM36]

Thanks Byprodriver and Gelbster. I have both, just never used the revers torx type socket before, so I should be covered.