so gas milage has been shitty on the integra i just noticed today a check engine light... jumped it and gave me a code 43
says fuel system or heated o2?
i think im gonna try and pop a o2 in who know when the last time it was replaced... anyone had this code b4? and how did u fix it?
havign this problem for about a week now

little info on the car is a 95 ls integra with a gsr swap... all motor, tranny, and ecu came from a donor car..
sometime the car will stumble like its out of gas?
i have all new maintance parts im about to do on the car tommorrow, plugs, wires, cap, rotor, fuel filter, o2

ANOTHER THING i noticed the ls and gsr fuel pumps are different part numbers? and im still on the ls pump.. maybe upgrade this? and just go to s 255?

i just seafoamed the car today as well

any help would be very helpfull
thanx in advanced

 

didnt fix it anyone know where to go from here?

 

O2 sensor.