1996 cadillac sedan deville .. it shows two o2 sensers ..one before the catalytic and one after .. how do i test to see if they are bad before buy new one ?

According to my info, you don't have a maf sensor. You do have a map sensor.

Changing the fuel filter isn't a bad idea prior to getting into the O2 sensor. You may want to consider replacing the TPS (throttle position sensor). Do an on board diagnostic test to identify the areas of concern. Most likely you'll get error codes for both the MAF sensor and the TPS.

located underneath the intake manifold remove it and disconnect the knock sensor unscrew the knock sensor. installation is reverse

would that be o2 sensor bank 2 which would be the o2 sensor after the catalytic converter the scan tool gives the code stored in trucks memory and that gives a place to start and if mech tested sensor and bad replace it

I would suggest checking your Oxygen sensor which will light up your service emission light. Check that and let me know Good luck

Try this,it should be it.

senser is faulty and needs changed. hope this helps?

HAVE THE SYSTEM TESTED BY THE DEALER, THERE SHOULD BE A FAULT CODE. BUT THE MOST LIKELY CAUSE IS THE AMBIENT AIR TEMP SENSOR.

Firing order 1-2-7-3-4-5-6-8 ..............1-3-5-7 back of engine near fire wall...........2-4-6-8 front of near radiator

1 in front of catalytic converter and 1 after