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Knock sensor harness location/access?

Thepurpr34
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Thepurpr34 Rookie

Thepurpr34

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Posted (edited)

Hello everyone.

I purchased a highly modified '98 r34 gtt this past February and have run into something completely unfamiliar... Wiring harnesses.

 

Purchased a new gtx3071r and after a few e-tuning pulls my knock stopped registering completely. Upon inspection one of my knock sensor connectors was cracked and fully disconnected.

I purchased a new knock sensor sub harness and am going to be tackling it this weekend and need a bit of guidance;

 

1) I have a intake plenum so accessibility to the knock sensors/wiring is nearly impossible, is it easier to go from the top and start removing the entire plenum or go from underneath?

2) Whereabouts should I expect amongst my main harness to find the connection for the knock sub harness? Would help if I knew a ballpark even mid engine'ish.

Any info whatsoever would be greatly appreciated. I've done lots of research and there seems to be very minimal info around the knock sensors & their harnesses for the rb25. I had a modified evo prior but unfortunately wiring & skylines are an entirely new world to me.

 

Thank you so much and have an amazing day!

 

- @ThePurpR34

Edited by Thepurpr34
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hardsteppa Grand Master

hardsteppa

Posted
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if it's anything like the r33 gtst - which it probably is - go in from the bottom, remove starter motor, and you will have plenty of room to get the rear plug. I only replaced the plugs, didn't pull apart the harness, but I believe the KNK sensors and fast idle are on their own loom, just taped together with the gearbox/alternator loom, so you either need to remove it as a whole, or try cut it apart with on car - removed the whole thing, and will almost certainly be easier for you.

The joined harness assembly will possibly be connected to the 3x gearbox connections, the alternator, the enginebay fusebox x2 points, the fast-idle, and knock sensors.....or possibly it will have other points too, can't remember, but that's the starting point.

When refitting the starter, ditch the top bolt and put a stud/nut in there instead - alot easier to get the starter on/off in future. 

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