i have been getting a sporadic code 23 - knock sensor - on my car (92 cx hatch with 95 B18C1 with a P72 ecu). now the light comes on every time the car is driven.

i have tested and inspected all wiring connections and wiring - only have 0.5 ohm resistance through the entire circuit. all connections are clean and tight. have even changed out the knock sensor.

car has meticulous service, and tune up history. timing has been checked, but will get checked again soon.

still getting the code 23. cel turns on as soon as i pass 3000 rpm while driving, or while sitting in neutral and holding the throttle...

noting has been done modification wise to the car recently to cause this.

could this be a faulty knock board? i have a parts ecu P72, but am unaware if you can change them out easily.

any thoughts or opinions?

 

It would be easier just to socket/chip the p72 ecu and disable the knock sensor in the chip :-)

http://phearable.net/ecu-chipping-en...g-service.html

 

not an option. i want to fix what i have now. unless we're talking of a super deal that is considerably cheaper than the website for a hondata s300.


anyone with any ideas?

 

Try the ECU on a known good car with a knock sensor. You may find it is not the ECU at all and that will help you rule it out.

 

+2 !

 

i did try a good ecu - did not fix it. i have a couple "extra" p72's lying around.
timing was also spot-on.

however in the process i discovered that the wire i had ran to the knock sensor had an intermittent open, as it had been stretched somehow, and made enough contact to get a good resistance value...

fixed wire, now problem is solved.