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Recomended Oxygen (O2) Sensor

Posted: Mon Jul 30, 2007 9:08 pm
by Soul Shinobi
I want to replace my oxygen sensor and wanted to know what brands worth looking at are. The OEM one costs $80. Would a Bosch one from the local auto parts store be good?

Posted: Thu Oct 25, 2007 3:03 pm
by MiataPaul
Yea the Bosch ones from AutoZone/advance/checkers/pep boys all should work ok for a 92 w/258,000. I have used them on several cars and never had a problem. I think they don't last as long as the OE, but at $20 that is not an issue!

Posted: Thu Oct 25, 2007 3:15 pm
by Soul Shinobi
Wow, I didn't realize it'd be that cheap! If I had any idea it would be I would have looked into it sooner. :)

Posted: Thu Oct 25, 2007 6:41 pm
by internetautomart
MiataPaul wrote:Yea the Bosch ones from AutoZone/advance/checkers/pep boys all should work ok for a 92 w/258,000. I have used them on several cars and never had a problem. I think they don't last as long as the OE, but at $20 that is not an issue!
WTF are you talking about $20???
Dealer list is $119.95
aftermarket runs in the $60-$80 range

Posted: Thu Oct 25, 2007 10:51 pm
by Soul Shinobi
Yeah, I just went to Pepboys and they wanted $69.95 for a generic one and $89.95 for the right one by Bosch.

$119.95 list for the OEM one, $86.36 from www.1stsubaruparts.com.

I'll have to junk-yard it.

Posted: Wed Dec 05, 2007 6:39 pm
by Soul Shinobi
Will the O2 sensor from a 1994 Legacy Turbo work on my N/A 1992?

Posted: Wed Dec 05, 2007 7:12 pm
by internetautomart
Soul Shinobi wrote:Will the O2 sensor from a 1994 Legacy Turbo work on my N/A 1992?
according to my info they are 2 different sensors, so I'd say no.

Posted: Wed Dec 05, 2007 7:28 pm
by vrg3
Yes, it will work. The only difference between the NA and turbo sensors is that the NA sensor has much longer wires; you can put it on a turbo and just tie the extra wire out of the way.

But I'd caution you against installing a used sensor unless you know it was only recently installed.

Posted: Wed Dec 05, 2007 7:36 pm
by denver_whitest185
Soul Shinobi wrote:Yeah, I just went to Pepboys and they wanted $69.95 for a generic one and $89.95 for the right one by Bosch.

$119.95 list for the OEM one, $86.36 from www.1stsubaruparts.com.

I'll have to junk-yard it.
do you know the part number?

Posted: Wed Dec 05, 2007 7:44 pm
by vrg3
If you want to replace your oxygen sensor on the cheap, get a 1-wire sensor. That may be the sensor MiataPaul is talking about.

Last time I bought one the guy at the parts store didn't know what I meant when I asked for a 1-wire sensor, and wouldn't let me go back to pick it out myself, so I ended up asking him for a sensor for a 1990 Yugo. It rang up at $16, and it's still doing the job in my car two years later.

Posted: Wed Dec 05, 2007 7:53 pm
by Fkyx
I imagine the ebay solutions are also viable then?

Posted: Wed Dec 05, 2007 7:55 pm
by internetautomart
vrg3 wrote:Yes, it will work. The only difference between the NA and turbo sensors is that the NA sensor has much longer wires; you can put it on a turbo and just tie the extra wire out of the way.

But I'd caution you against installing a used sensor unless you know it was only recently installed.
that would explain why I showed 2 different #'s

Posted: Wed Dec 05, 2007 8:04 pm
by vrg3
eBay solutions?

Posted: Wed Dec 05, 2007 8:12 pm
by Fkyx
O2 Sensors that are available on Ebay...

Posted: Wed Dec 05, 2007 8:19 pm
by vrg3
If they're just oxygen sensors and they're from a good brand I don't see why it would matter where you buy them.

Posted: Wed Dec 05, 2007 8:33 pm
by Soul Shinobi
vrg3 wrote:But I'd caution you against installing a used sensor unless you know it was only recently installed.
Why is that?
vrg3 wrote:If you want to replace your oxygen sensor on the cheap, get a 1-wire sensor. That may be the sensor MiataPaul is talking about.
How would I hook one of those up?

Posted: Wed Dec 05, 2007 9:15 pm
by evolutionmovement
The single wire is the power lead and the body grounds through the exhaust. Additional wires are for wired grounds and the heating element. The exhaust ground isn't as reliable and the heating element allows the sensor to work sooner for better cold-start emissions. Find your O2 power and just connect the single lead to it. I believe ours are 3-wires, so you have a power for the heating element as well as a ground wire. I don't know which are which.

Posted: Wed Dec 05, 2007 9:21 pm
by vrg3
Steve, what you're calling the "power" lead is more accurately called the "signal" lead.

Yes, our sensors are 3-wire. The two additional wires are for the heater, with no defined polarity. So, the sensors actually still rely on their mounting to the exhaust for the signal ground.

The only difference between a 1-wire sensor and a 3-wire sensor is that the 3-wire sensor is heated and so reaches operating temperature much faster. Once they're warmed up, they are exactly the same.

Posted: Wed Dec 05, 2007 9:23 pm
by Soul Shinobi
Ah, I see. This means that a single wire wouldn't give as good fuel economy, unless you did long trips all the time, then the lack of a heating element would be trivial. My problem is that my car is in a state of good tune and I drive carefully but I only get 24 mpg max when I'm sure I should be getting nearly 28.

I'm pretty sure the O2 sensor is not working like it should because it doesn't fluctuate for a many few seconds at a time when I hooked up the B10 scan tool (yes I made sure it warmed up and exited open loop).

Posted: Wed Dec 05, 2007 9:44 pm
by vrg3
In principle, yes, a 1-wire sensor would get yield worse fuel economy. I don't think it's that big a deal, though, because the sensor still warms up fairly quickly, and the ECU doesn't use the oxygen sensor signal until the engine's warmed up anyway.

It does sound like your sensor's not doing its job. Maybe it's clogged up so it's slow to respond?

Posted: Thu Dec 06, 2007 12:58 am
by ciper
There are only two types of true oxygen sensors around. Either narrow band or wide band. The narrow band is what many cars use and they vary by number of wires (heater and grounds) and the mounting method (screw in or bold on). There are a few specialized units but for the most part you can retrofit any of the like type to your car.

You can get universal Bosch sensors for pretty cheap that work great and are essentially OEM.

Posted: Thu Dec 06, 2007 3:56 am
by internetautomart
oops

Posted: Thu Dec 06, 2007 3:58 am
by internetautomart
there is more to o2 sensors than you are aware of.
trying to adapt any old one can cause issues for people than have to emision test their or care about things working correctly.
different sensor have different resistances (ford does that). there are "o2" sensors that aren't an o2 sensor at all (toyota has those).
I deal with cheapskate repair shops all day long and NONE of them will take a universal o2 anymore because they just aren't right.

Posted: Thu Dec 06, 2007 4:02 am
by ciper
internetautomart wrote:there is more to o2 sensors than you are aware of
I edited my post just for you. Sure there are specialized versions but overall the parts are the same from the manufacturer. Most of the differences with narrow band units are - mounting type, housing, connector and the inclusion of a heater and grounds. The function of the actual sensor is the same.

Someone check this for me but The Bosch part #15726 is the 3 wire universal that will fit our cars and the Bosch part # 15732 is the 4 wire universal for our cars

Posted: Wed Dec 19, 2007 2:52 am
by courtjesterclown
ok, so i got the Bosch 3 wire universal, and it has one black wire and two white wires. But on my stock plug there is one white, one black, and one red. When i tried to hook it up today, my car ran like crap, threw black smoke cuz it was running so rich and wouldnt even idle. I unplugged the oxygen sensor, and it ran fine. So obviously i hook the black to the black, but which wire from my plug in hooks up to which wires on the bosch sensor (1 black, 2 whites).