ok so i just got a new custom cat-back exhaust from a local muffler shop, for my 95 GSR, and they didnt touch the cat at all, and as soon as i leave the shop my check engine light comes on, any ideas on how i can check for free or what it could be?

 

OBD1...Jump the two wire connector near your passenger side shock tower...Under your dash, glove box side...Use a paperclip and then turn switch accessories on but not car and watch as your Check Engine blinks in a series of dashes....

Long pause = 10
Short pause = 1

2-3 seconds in between it will read another code if there is multiple things wrong with your car...

 

ok, its the O2 sensor heater, what does that mean