RX7Club.com - Mazda RX7 Forum

RX7Club.com - Mazda RX7 Forum (https://www.rx7club.com/)
-   3rd Generation Specific (1993-2002) (https://www.rx7club.com/3rd-generation-specific-1993-2002-16/)
-   -   Unplugging Knock Sensor?? (https://www.rx7club.com/3rd-generation-specific-1993-2002-16/unplugging-knock-sensor-976443/)

ppritchard Nov 10, 2011 05:53 AM

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

MazdaSpeedDan Nov 10, 2011 06:05 AM

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.

goalguy02 Nov 10, 2011 09:39 AM

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!

ppritchard Nov 10, 2011 11:38 AM

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

Bowtie7 Nov 10, 2011 11:38 AM

Code 5- knock sensor. Will cut boost and retard timing-confirmed!!!

Speed of light Nov 10, 2011 01:06 PM

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.

ppritchard Nov 11, 2011 05:45 PM

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

Speed of light Nov 12, 2011 04:08 AM

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.

goalguy02 Nov 13, 2011 09:32 AM

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.

dakota's rx7 Nov 13, 2011 09:46 AM

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

dakota's rx7 Nov 13, 2011 10:00 AM

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


All times are GMT -5. The time now is 08:43 AM.


© 2026 MH Sub I, LLC dba Internet Brands