I have a 92 camaro RS 3.1L. The service engine light comes on just after starting it up. I pull the code and it is a code 43. Whic is a low voltage at the electronic spark timing circuit. The further I dig they say it comes from the knock sensor. Know is this so and were is the knock sensor located on the 3.1L engine?

 

Yes,the knock sensor circuit is the culprit..the knock sensor is on the block next to the starter.Quick check is removing the wiring and checking for voltage w/key on.Should be 4-6 volts..if it is then the sensor itself is probably bad.If not 4-6 then you will need to look into the wiring.If its over 6 volts its either shorted to voltage...if its less then 4 volts then its either shorted to ground or either could be a bad ecm.