Saturn 2001 L300 Bad O2 Sensor?

Just because it says your o/2 sensor is bad doesn't always mean that is your problem, but it's a good place to start. Oh that should be your #1 upstream sensor which is before the cat. You might even get lucky and find a burnt wire or something easy.

These numbers dont pass the sniff test... MAP should be 17-21..not less than 10. Also what were the O2 voltages? I would start by checking manifold vacuum with a gauge and eliminating mechanical problems, then check the 02 sensors for shorted heater circuits and voltage output. HTH Ben

Thanks Ben, I will check that.

Then you don't understand what MAP is.

BARO minus vacuum = MAP