Knock Sensor Rewire Debate?

SupraLover

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Apr 13, 2005
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Ok, I've looked at half a dozen knock sensor (KS) rewire instructions which conflict one another..One author says to ground the new KS wire on both ends, the ground on the KS end would be on the ballister connected on the lft. strut tower, and the ecu end would be on the nut for the ABS computor bracket...another author says NEVER ground both ends, only the ECU end should be grounded, and even here there is a split on opinion, as one person says to ground it on the ABS computor bracket, and another says ground it in the same place as the original Knock Sensor ground shield is wired, where ever that is, he states to look in the TSRM for the wiring diagram. (have you ever looked up TSRM on line to find out where the Knock sensor is originally grounded? Give me a break, just tell us please! Anyway, do I ground it on both ends? if not, where do I ground it on the ECU side? ....what are your thoughts?.....Thanks for your time....
 

steve_mk3

Supramania Contributor
Mar 30, 2005
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my opinion-
You only ground one end - the ECU end.
I forget where I grounded the wire to, but I do know the first time I attachede it I did not get a good ground and ended up running the wire to a known good ground( checked it with an ohm meter)
 

shaeff

Kurt is FTMFW x2!!!!
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Mar 30, 2005
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Ground only the ECU side. Grounding both sides creates ground loops. I always tell people to ground it to the large support bar behind the dashboard.

I'm sure JetJock will come in here and school us. :) (at least I sure hope he does!)
 

jetjock

creepy-ass cracka
Jul 11, 2005
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How did Toyota do it? They grounded it at one end. The reason is what shaeff said. Factory wiring grounds the KS shielding to E1 (chassis ground) by way of Ground Point B at the intake manifold. If you "ever looked up TSRM on line to find out where the Knock sensor is originally grounded" you'd know that.

Grounding as shaeff said will work but I prefer to ground to E1 at the ECU connector or the original wire. Same difference...
 

SupraLover

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Apr 13, 2005
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Well there we have it! Ground only one end, the ECU end, and ground it to the E1 at the ECU connector, or in the alternative, to the large support bar behind the dash....I appreciate your input
 

isnms

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Mar 30, 2005
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^ You didn't read what he wrote:
jetjock;1333636 said:
...by way of Ground Point B at the intake manifold...

Tis where I grounded mine. Easier to ground the shielding in the engine bay to the manifold than try to strip and solder to another ecu wire.
 

jetjock

creepy-ass cracka
Jul 11, 2005
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Right. Note I didn't say it had to be grounded at the ECU end but at one end only. It's just that when running replacement wires it's easier to ground at the ECU. Regardless, the ground ought to be on E1 rather than another point on the chassis so that the shielding and ECU share the same ground point without depending on the chassis to connect them. You want this because even though the chassis is supposed to be electrically the same throughout it's possible for a difference in potential to exist between two points on it. That potential is also the reason only one end should be connected.

Lmao @ Ian....