can't get rid of the code. i'm currently running a base map until i can get it tuned. running hondata s200B. i replaced a new o2 sensor, fuel filter, fpr to aem, running rc440 injectors. all been done in the last two days. reseted the ecu by unplugging it for a while goes away but when i cruise at 70mph at like 3k rpm it then comes on again.
94civic hatch b16a turbo

 

code 43 is a rich/lean fault.

It's usually from a bad O2 sensor, which could result from running too rich to begin with (it can foul the sensing element) clean the sensor with compressed air (blow all the soot off), get it tuned, then clean the sensor again, and you should be good to go.

 

The ECU's fuel trim parameter has reached its max or min. This is due to the O2 sensor telling the ECU that the mix is so rich (or lean, but probably rich since you're on a basemap), that it needs to lean the mix out. So the ECU starts using its fuel trim parameters to get the O2 sensor swinging again. If it uses up all its range in trying to do so, you get the code.

So either your O2 is really duffed or your a/f ratio is just too rich for the ECU to deal with. Since you tried a brand new O2 sensor but did nothing to the fuel maps, you're going to constantly get this code and foul out O2 sensors.