Knock sensor rewire

SupraKid

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I know this has been covered many times, but I feel more comfortable asking and getting current information then piecing together threads that have different opinions and what not. Got code 52 yesterday and from what I understand more then likely I’ll need to rewire the ks’s. Question is 1, how can I trigger the code coming back to confirm it and 2 if it does come back can I use this kit http://www.yotaconnectors.com/product-p/sup-003.htm. Splice the wire into a bit of what’s coming off ecu and ground the other wire to the body or something? Any help is appreciated.
 

plaaya69

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That knock sensor kit what I am using right now on my new engine harness. It is very high quality and comes with the female pin for the ecu already assembled so no splicing is needed. You only need to ground the 2 shielding wires for each sensor. Before you rewire it, have you ever changed the knock sensor/'s before on your motor?

From the factory per knock sensor you just have the KS signal wire and the shielding ground wire that ties into the E1 ground pin on the ECU. The same knock sensor grounds ties into the CPS shielding ground also so you have 3 grounds that tie into one grounded section in the engine harness loom for the 7mGTE.
 

SupraKid

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Awesome! Was wondering about the pin didn’t see it on there, even better, never touched the factory knock sensors before. So do I use those factory ground? Or use a good ground elsewear
 

plaaya69

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From factory it was all grounded on the lower intake manifold. That is where I am grounding mine but be aware the way that kit comes is one of the shielding ground wires is close to the knock snesor and the other knock sensor shielding ground wire is close to the ecu. I am keeping mine as it came factory with a 3 point ground tie-in like it came but you should have both shielded wires grounded on the motor.
 

SupraKid

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Gotcha that’s where I was confused, looked like the one came off by ecu and that didn’t seem right to me, probably gonna take car out and see if code trips, then I’ll go ahead and order the kit. Thanks for the help
 

andrew_mx83

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From factory it was all grounded on the lower intake manifold. That is where I am grounding mine but be aware the way that kit comes is one of the shielding ground wires is close to the knock snesor and the other knock sensor shielding ground wire is close to the ecu. I am keeping mine as it came factory with a 3 point ground tie-in like it came but you should have both shielded wires grounded on the motor.

Not sure if I've followed you correctly, but generally speaking the shield of a shielded cable should only be grounded at one end. If you ground both ends then it's not actually acting as a shield.
 

SupraKid

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Drove car today all was well so far, going to wait until it pops up again or gives me a problem. Car spends most of the time in the garage anyways. Just trying to see what I’ll be getting into at some point
 

plaaya69

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Not sure if I've followed you correctly, but generally speaking the shield of a shielded cable should only be grounded at one end. If you ground both ends then it's not actually acting as a shield.
You are correct, each of the 2 knock sensors has one shielded ground wire per knock sensor. It is just with the kit each of the ground's is on a different end (one ground wire coming coming out near the knock sensor the other ground is coming out near the ecu for the other knock sensor).

I just dissembled a complete engine wiring harness for a 87 7mGTE there is a 3 point tie (with the CPS shield ground added) in about 1 foot away from the ECU connectors where it all ties together with factory crimp connectors like this http://www.yotaconnectors.com/product-p/spl-c02.htm .
 

3p141592654

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That is a so called E1 ground. It needs to be tied to the intake manifold with the other E1s. I cannot tell from the pic if the two brown wires of the new harness are separate, but they need to be tied together somewhere and then on to the intake manifold.
 

plaaya69

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That is a so called E1 ground. It needs to be tied to the intake manifold with the other E1s. I cannot tell from the pic if the two brown wires of the new harness are separate, but they need to be tied together somewhere and then on to the intake manifold.
Yes, each knock sensor wire has its own brown ground wire and that is what makes it a bit hard is each ground is on different ends. They should have both came with each ground on the same end just like OEM so it is easier to tie it all together.
 

Hybrid

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Glad I found this thread. I am checking and renewing my harness whilst the engine is away getting rebuilt.

I saw recently Ken Henderson changed over to newer 1JZ knock sensors, so thinking might do the same. Anyone see any issues with this?

Otherwise was looking at the linked 7M rewire kit. I would need to shorten though as RHD, but no big drama there.
 

plaaya69

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Glad I found this thread. I am checking and renewing my harness whilst the engine is away getting rebuilt.

I saw recently Ken Henderson changed over to newer 1JZ knock sensors, so thinking might do the same. Anyone see any issues with this?

Otherwise was looking at the linked 7M rewire kit. I would need to shorten though as RHD, but no big drama there.
If you are on the factory ecu, I would personally just stick with the 7m knock sensors unless you are running a standalone. Do you plan on running a standalone?
 

Hybrid

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Yep on the factory ECU currently. I wouldn't go stand-alone I don't think, more likely a piggyback such as the DET3.

There is rumours the 93 A70's had the newer sensors, bit I can't find any evidence to support that.