Chek engine with P0131 & P0151
 

I have about 400 miles since installing a Stillen supercharger and the car has been running great but today at lunch the check engine light came on and is reading codes P0131 & P0151-low voltage to both O2 sensors. Anyone ever had this happen or any idea what would cause both to give a code at the same time?

Do your AFRs look strange? and which bank 1 or 2? If it isn't bank 1(AFR sensors) I wouldn't worry too much right now.

P0131 - Oxygen O2 Sensor Low Voltage (Bank1, Sensor2)
P0151 - Oxygen O2 Sensor Low Voltage (Bank2, Sensor1)

Different banks, different sensors.

IIRC (heavy on the if, my memory ain't what it used to be):
Sensors 2 are just used to check the cats' performance.
B1-S1 is used for engine control.
The ECU doesn't use any Bank 2 sensors (MAF, Intake Air Temp, &c) for engine control.

Thanks for the info guys. We believe it's caused by the car being to rich on the Stillen tune. Since installing the Supercharger the exhaust tips get charcoal black fast so I think the same is happening to the O2 sensors. It's going to the dyno Saturday for a real tune.