So awhile ago I was reading a thread about the three wires that hook up to the Knock sensor from the ecu and how there was a black wire and some people didn't know whether or not to hook it up to ground and some did. Well today I talked to John from J&S and he read that thread and asked me to post up that the only wire to hook up is the clear wire to the knock sensor, the other wires are in there for another reason that I forget but it's i think to shield the clear wire and serves no other perpose. He wouuld post this himself but doesn't have an account to post this info. I couldn't find the thread that this was about.

John has an account on here....... at least he use to.

If I remember right one wire (yellow) is for a window switch so you can run nitrous and the J&S will retard your timing for you.

wasn't there a write up on here about hooking the J&S up? or is that what you're talking about?

thats what he is talking about.

John has an account on here....... at least he use to.

If I remember right one wire (yellow) is for a window switch so you can run nitrous and the J&S will retard your timing for you.

The wire now is brown if it was yellow. Yeah John said he didn't have an account.

hey brandon how much did your build total cost?

hey brandon how much did your build total cost?


I'll have to add up all my reciepts but it's way less than a full kit for SVT's.

Ummm......sorry but if I do not hook the black wire your referring to then the J&S does not Function at all.

Thats what the other thread discussed. Both need to be attached. The CLear to Knock, and Black one thats paired goes to ground.

I tried just one wire, and the J&S does nothing at full sensitivity and knocking on the sensor at 3k with a hammer.

Ummm......sorry but if I do not hook the black wire your referring to then the J&S does not Function at all.

Thats what the other thread discussed. Both need to be attached. The CLear to Knock, and Black one thats paired goes to ground.

I tried just one wire, and the J&S does nothing at full sensitivity and knocking on the sensor at 3k with a hammer.

Are you unhooking the ground wire that goes from the main harness or the ground wire from the loom that's with the clear knock wire cuz mine works without that hooked up. Also did you plug the vac port on the J&S when tapping with a hammer? if not plug off the vac port to the J&S cuz the unit will arm when no vac is being drawn thu the unit.

The one with the clear.

what about vac port on the J&S when you tap the knock sensor?

I don't use it at all. So the unit is always functioning

mine works fine with the vac port hooked up you might wanna contact John from J&S then and see what's happening, also check the build date of your unit, he said the older units have some issues and he had to replace something in the or the whole unit.

Already have done all of that. I have the new Vampire for sure!