ok.. well i keep getting this code. dont know why. my whole ignition system is aftermarket. everything is firing fine. but every day or every other day ill get a check engine light and its this code. the guy who i take my car to checks the car out.. finds nothing wrong and clears the code. *btw he/his shop only works on 82-02 f-bodys and vettes, so he knows his **** when it comes to TPI*

 

Code 43 is an ESC circuit code If the ckt 496 is open or shorted for .5 sec it will set a code, it could be a bad knock sensor connector or any other connector with a bad connection. Check the grip of the male to female pins on the connector and check associated wiring.

 

is this a must fix if i want to get nitrous *150 shot* or is this just a annoying code?

 

For running nitrous you probably want it fixed. look around at your connectors you may get lucky.