Oxygen sensor

[HUM GOOD]

Originally Posted by IRA51

you can buy a scanner and check the o2 switching rate through the OBD DATA PORT..but if you want a/f ratio readings and want them to be accurate you will need to take the readings with a gas anilizer upstream of the cats . if your switching rate iS in the normal range you should be fine.

Can I tap into the sensors in the exhaust between the motor and the cat.....or do I need to drill in a seperate one for the monitor?