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Unplugging Knock Sensor??

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Old Nov 10, 2011 | 05:53 AM
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From: Longwood FL
Unplugging Knock Sensor??

With a stock computer, if you unplug the Knock Sensor -- does it give you a Check Engine Code? Trying to see if the current code is impacting performance by changing the timing whenever the knock sensor error comes up.

Also, does anyone know if the stock wire will "reach" the the rear housing?

thanks
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Old Nov 10, 2011 | 06:05 AM
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Yes, if you unplug the knock sensor you will get a knock sensor code. I believe it is 05. Knock sensor can infact retart timing as stated in the FSM.
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Old Nov 10, 2011 | 09:39 AM
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Any fault with the knock sensor puts the car into limp mode also. I had an issue with mine and ended up being old wiring harness. Cut out the bad portion and soldered in new shielding wiring and voila!
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Old Nov 10, 2011 | 11:38 AM
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Where does the Knock Sensor "plug" run to? I can't see it. Do you have to take the uim off to get to wherever it plugs in or am I looking in the wrong spot?

Thanks
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Old Nov 10, 2011 | 11:38 AM
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Code 5- knock sensor. Will cut boost and retard timing-confirmed!!!
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Old Nov 10, 2011 | 01:06 PM
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If you remove the knock sensor, the input lead needs to be biased with a pulldown resistor to about 3-->5V to prevent a cel code.
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Old Nov 11, 2011 | 05:45 PM
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Has anyone moved the knock sensor to the rear housing and if so, did the wire reach or did you have to extend it?

thanks
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Old Nov 12, 2011 | 04:08 AM
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Yes I moved mine to the rear housing and I had to extend the wire for it to reach, including the shield. I used a connector at the point where the stock wire is broken out of the EM harness to join the extension. If your wiring is in good shape, you might be able to get away with something simpler.

I also put a Bosch knock sensor in the front housing for the J&S knock retard unit. It works fine in this configuration.

Hope this helps.
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Old Nov 13, 2011 | 09:32 AM
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I had to remove the alternator to get at the knock sensor wire easier. Got some shielded wire from radioshack and patched my harness where it shorted.
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Old Nov 13, 2011 | 09:46 AM
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So if I'm running an s5 tii engine in my s4 na but I have tii wiring harness with trek 2.1 ecu i still need the knock control box? The knock sensor is still there but do I need the control box
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Old Nov 13, 2011 | 10:00 AM
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Also it's a jspec s5 engine it has the knock sensor on the passenger side not on the driver side I also have s4 tii wireing harness what needs to be done if i need to run the knock sensor
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