what are signs of an old and or failing o2 sensor?

[musthavemuzk]

after reading the thread about changing one and then seeing that it might be a good idea to change it due to age......i was wondering what are signs of the sensor showing age?
Monty

[MaD]

From what I've been told, they really don't give any signs unless they're dead. Or unless they're throwing codes left and right (which should set off your "check engine" light)

Optimally, if you have the loot, you should change these every 4 oil changes or so. (so, roughly every 12,000 miles, which is the same "Tune-Up Time" interval you should be changing your plugs, fuel filter, etc at.).

They "technically" can last longer, but, I dunno, I suppose they'll get all corroded and so on and well, I personally don't like it (only now that I'm finally learning how to work on my car and I have some side cash)...

However, they're not too cheap! ($50 for Delco, but NEVER get anything else!, I dunno why, I just get that feeling)

But anyways, yea
-MaD-[/quote]

[crc]

I've heard they are supposed to last much longer than that. I'm almost positive the one in mine was the original and my car is going north of 160k miles. Lately I've had terrible fuel milage, noticeable fumes when I restart the car after I've driven it a while (probably too rich air/fuel mixture) and rough idling (or at times the car refuses to hold idlle and yo-yos back and forth) I'm not sure if all of these are O2 Sensor related but that's the first thing I'm changing. Everything else seems to run just fine, engine wise. Damn, you gotta love the 3.1L, not very sexy but it's a workhorse.

[Anonymous]

I doubt your 02 sensor is your problem. With 160,000 miles it wouldn't hurt to change it anyway.
My gas mileage has went down some, it smells when starting after driving, etc... I just changed my O2 sensor and nothing changed.

[musthavemuzk]

hmmmm
well the idle is rougher then when i drove the car home mid may. at that time it had 115,000 ticks. this past monday i gave her her third oil change. so that puts her about 9,000 additional ticks on the clock in three months.
i have noticed the ride is slightly rougher (suspension related) as well as a rougher idle. no noticeable fumes though.
i have been running premium in her to see the difference in MPG. so far on long trips i notice about 2-3 more per gallon. in town driving and mixed town and highway no difference noted.
this has been since the last oil change.


the first week i had her i did plugs and wires and tranny filter and fluid.
replaced the air filter after a couple months.
am saving some cash for rear shocks and front struts. just gotta pick the brand. and get the cash. also am planning a front tower brace as well as a rear sway arm ( i think that is what it is called.) with mine being the standard plain CS it is a 28mm hollow (so i have been told) the GP or was it the euro or z34 i think has a 30 not sure if it is solid or hollow though. then i think it was the regal GS that had the 34 solid. i may be confoosed on those, but i know i want a dif one. i hope to do energy suspension bushings as well.
i am all for straight line, but i am not willing to give up handling.

but with this talk about the o2 sensor i thought i would ask about it.

also saving for a k+n. not sure if i am gonna do the drop in or a cone though. the drop in i can get in town for 60. they have to order it though as they donot cary them onhand.

alot planned, just not enough money at one time to do it all. so it comes in stages.
wheels and tires would be first but with winter coming fast they will wait til spring.

Monty

[per0781]

arent there 2 O2 sensors on w bodies.....thats what i heard?

Paul

[MaD]

I believe any car with ODBII (which is probably any car that is 96 or newer) has two o2 sensors.

I'm almost positive that all OBDI cars only have 1 o2 sensor, W-body, or not.

[NORBI]

My 88 CS has little over 190k miles and i never changed sensor and i still have original one on my car and service engine light doesnt come up at all and if it did it was caused by MAP sensor. I would drive it till it really starts showing light all the time.

NOT TRUE!!! i have 174,000 miles on my '92 Z34...the o2 sensor is plugged in, nothing more, nothing less, i guess mine got bumped out of socket and my check engine light would come on if i let it idle for awhile, note: it happened AFTER an oil change...next oil change i had the mechanic look at it, he pulled it out, cleaned the connectors, plugged it back in...never came back on since...so! have your next oil change come around and just have him clean the connectors and plug it back in, should work, my car's idle rate is all messed up too, anyone gimme some clues on that?? when i start it, it'll high idle and accelerate for me...if i pop it in neutral RPMs go to 2500 and idle there...any clues??