My 2005 G35 Coupe has been showing a constant P0327 Knock Sensor Circuit Low Input diagnostic trouble code (CEL, SES, DTC), so I decided to check out the knock sensor. A poster on my350z mentioned he had the same problem, but it turned out to be the knock sensor harness, not the knock sensor itself. I had Lokey Infinity price a knock sensor harness and they said it cost $843. Wow! I think I'll check things out before I tackle that. The knock sensor itself was only $51.

I took the top of my motor off today to get to the knock sensor and harness. You have to remove a lot of stuff to get at one crummy knock sensor bolt.



Here's my knock sensor. I'm kinda concerned because it looks like the knock sensor harness is pulled backwards. I would have tried to have the harness make a gradual curve around towards the back of the block. Maybe there isn't enough room for that.




Here's where the cable runs out the back of the block.



Has anyone replaced this harness? Does it really cost $843?

Thanks for any help.

 

Turns out that the cable was smashed between the transmission and the engine block during a transmission replacement. You can see it in the picture above.



There's the bad piece.

All repaired and replaced, now.

Thanks to Matt (Zu L8r) for giving me his spare cable.

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Wow. Good find. It's good to know the failure was inflicted and not just some random failure of the wiring itself.