Any way to check if your oxygen sensor still good??

[JT-KGY]

Are there any ways to find out if (all or which) of your oxygen sensors are still working properly (for 96+ OBDII cars)???
I was told that you can do some "Check Engine" tricks on 95 cars that will read off the computer which oxygen sensor need to be replaced...

My concerns are my car always got this slight gas smell from the exhaust air... (Maybe b/c it was idle for a while.. I'll double check)
Also, heard that oxygen sensors could be bad as early as 40k miles.. I have 45k now... so..

Another reason I am asking is that.. these sensors are covered under warranty.. and they are $100+ EACH!!... that's $400+ if I want to replace them all!!...so really wonder if there's anyway i could make sure which are bad before replacing..

Thanks,

[jww///95]

A bad o2 sensor will trip the check engine light just on an obdii car just the same as it will on the obdi's. With 45k on the clock I wouldn't worry too much about the sensors unless you really noticed a loss of performance. I just finished up some spring 70k maintenance on my '95 a month ago and I changed the plugs, fuel filter, and o2. Before the replacements, the car seemed to have a lag at around 4k rpms and gas mileage had suffered my about 1 or 2 mpg. Since the changes, the car runs great and the mileage is back up, but keep in mind my car had 70k on the original o2 sensor.

Sorry for the rambling, but just put it this way... with 45k don't worry about the o2's until a mil light is tripped.

J-

[BMWguy206]

JT-KGY,

I'm gonna have to agree with jww///95 on that one. Monitoring oxygens sensors on your M3 is kinda difficult and of course the only diagnostic computer that will give you better readings are the ones from BMW. I would replace them only if they set a check engine light, which I have done (replaced both pre-cat O2 sensors)

When does the smell occur? If it happenes anytime before the coolent temp. reaches normal operating temp. then its not the O2 sensors since at cold start, the DME doesn't take any inputs from the pre or post catalytic conv. sensors. Just coolent temp and air mass signals.

I haven't seen the post-cat O2 sensors go out alot on these engines so you dont have to worry much about that.

Hey, if you do get a bad O2 sensor and you are out of warranty, I can make house call to you when I move back to CA mid summer so you wont have to spend too much errr.. somewhere else =)

What city do you live in anyways?

[JT-KGY]

Jon,

Sorry.. just saw this post..
:)

Very nice offer of you and much appreciated...
I live in Monterey Park.. (91755)..which is right south of my mom's place Alhambra (91803)..
I am also in Alhambra alot... so if you do end up working in New Century.. I'll pay you a visit.
:)

P.S. I notice that you have techno violet too, don't you just love that color..