Several weeks ago, the 97 started getting terrible gas mileage and stinking (was running rich and no cats to clean it up). I pulled codes and got a bunch of codes for a front O2 sensor. I replaced both front sensors and my mileage is better and the car doesn't stink, but now I am getting a code for one of the back sensors:
P0136 02 Sensor Circuit Malfunction (Bank I Sensor 2)
I have an MIL's on the rear sensors now. For the computer to be happy, does the MIL require a working O2 sensor? I suspect that sensor was barely happy before, then because of the bad front sensor the engine was running way rich and that was enough to kill it.
Do the rear sensors have any effect on mileage or are they PURELY for emissions? Also does the MIL need a working O2 to function properly? I'd like to get the check engine light off, but I sure don't want to spend 70$ on rear O2 sensors when they have no effect on anything!
P0136 02 Sensor Circuit Malfunction (Bank I Sensor 2)
I have an MIL's on the rear sensors now. For the computer to be happy, does the MIL require a working O2 sensor? I suspect that sensor was barely happy before, then because of the bad front sensor the engine was running way rich and that was enough to kill it.
Do the rear sensors have any effect on mileage or are they PURELY for emissions? Also does the MIL need a working O2 to function properly? I'd like to get the check engine light off, but I sure don't want to spend 70$ on rear O2 sensors when they have no effect on anything!