Bank 1 & Bank 2 Oxygen Sensors

Before you go ripping out and replacing sensors. Make sure you don't have any holes or tears in the tube between the MAF and the throttle body. Just went through a very similar situation and checking for that would have saved me a lot of time.
 
Our cars don't have 'bank one' or 'bank two'. We have upstream and downstream. They are different sensors. The upstream one is the important one,... the downstream is almost a 'dummy' sensor.

We have two sensors in the same bank.
 
I am experiencing the same issue, but I am not sure what the solution is. I have replaced the intake tube a year ago, and I can confirm that there are no holes in it. The McParts store said specifically that the code does NOT mean the sensor is bad. The car still runs like a champ, gas mileage isn't suffering. Not looking to replace a whole bunch of things that aren't broke, but my OCD is telling me the light must not stay on.
 
Hey all. I am getting this code too. I have a yellow P5 automatic 2003.

I Had the air intake tube replaced recently because there were tears in it and haven't had any issues for months. Now I get P0031 when I start the car. I connected the OBD reader to it and both sensors show data when I accelerate.

When I clear The code, the code comes back upon car startup and stays on until manually cleared. Sometimes it does not come on atall, but it's happening more and more.

Where is the bank 1 sensor 1 located? Is it something I'll be able to get to from the top of the car or will it need to be hoisted? Thanks!
 
Also, does anyone know the part number for the sensor? Someone posted an Ebat link to it here, but the item is long-gone.

https://www.mazdas247.com/forum/showthread.php?123819066-Oxygen-Sensor-Change-with-Photos

Parts manual, P. 334, under the Exhaust section there are these, are they what I am looking for?
Probably ZM03-18-861A-9U as I have a Canadian car.

15 Sensor, Exh Manifold Oxygen
1.6L Eng
w/Calif Emission ZM03-18-861A-9U
w/o Calif Emission ZM01-18-861A-9U
1.8L Eng FP49-18-861-9U
2.0L Eng FS7N-18-861-9U
 
Hey, what do you guys think of this idea...
I ordered the part from my local shop - fully returnable. If I just plug in the new sensor (without installing it into the manifold), and the P0031 code goes away, then I can be certain the old sensor wasn't working optimally, right?

Of course, I know that a bunch of other codes will start popping up when I start the car because the sensor isn't installed, but at least I'll rule out the actual sensor as the problem.

This is what I did with my broken ABS sensor and it worked...I plugged in the new sensor and the error code was gone, because the computer no longer detected voltage issues in a bad sensor. The I proceeded to have the ABS sensor installed by a mechanic and everything has been fine since.
 
Hey, what do you guys think of this idea...
I ordered the part from my local shop - fully returnable. If I just plug in the new sensor (without installing it into the manifold), and the P0031 code goes away, then I can be certain the old sensor wasn't working optimally, right?

Of course, I know that a bunch of other codes will start popping up when I start the car because the sensor isn't installed, but at least I'll rule out the actual sensor as the problem.

This is what I did with my broken ABS sensor and it worked...I plugged in the new sensor and the error code was gone, because the computer no longer detected voltage issues in a bad sensor. The I proceeded to have the ABS sensor installed by a mechanic and everything has been fine since.

Yeah, theoretically. The heater is activated right away after you turn the key on.
 
How hot does it get, i guess I'd better make sure it's not around anything too flammable or resting on top of something that will melt, right? For safety?

Thanks.
 
You should just install your new O2 sensor...
The computer knows if your old heater is burned out... No current flow...
I'm sure you can be more than 95% sure the new sensor will fix your problem... It's like a burned out bulb.
Stop far tin around and be done with it... O2 sensors do wear out...
 
You should just install your new O2 sensor...
The computer knows if your old heater is burned out... No current flow...
I'm sure you can be more than 95% sure the new sensor will fix your problem... It's like a burned out bulb.
Stop far tin around and be done with it... O2 sensors do wear out...
i decided to take that advice and stop far tin around, unfortunately Canadian Tire ordered the wrong part for me :( They ordered a downstream (post-cat) sensor.

Does anyone know if the upstream and downstream sensors are interchangeable? I read somewhere that the only difference between the two is that the cable is a different length...is there any truth to that?

Sadly, if I go with the upstream, they're asking $135 for an NGK, $175 if I want a Denso :( i don't mind ordering from the Internet as long as it's returnable...I'd rather just use what Canadian tire ordered me (the downstream) and be done With it, so if anyone knows if these two parts are interchangeable, lemme kno ya?
 
i decided to take that advice and stop far tin around, unfortunately Canadian Tire ordered the wrong part for me :... so if anyone knows if these two parts are interchangeable, lemme kno ya?

Almost positive they are not the same part... (or they would list them as such)

Rock auto is great for shipping to Canada...

 
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Almost positive they are not the same part...

Rock auto is great for shipping to Canada...
actually, it's funny that you mention rock auto. I was just looking up parts there in the last hour or so and I can get the walker upstream sensor and the socket to install it for about 60 bucks Canadian delivered. That's pretty amazing. I always assumed it rock auto was one of those places that charged minimum $50 shipping to Canada and made you pay asinine duties and taxes on top of that. I think I'll stop far tin around and get the Walker part and go that route, unless walkers are sh#%tty parts?
 
...and get the Walker part and go that route, unless walkers are sh#%tty parts?

The Walker's are "hearted" meaning lots of people ordered them.

If they were crap, and all being returned, Rock auto would stop selling them ..
 
.... and the socket to install it for about 60 bucks Canadian delivered.

You don't really need the socket... Just cut the wire of the old sensor and use a regular socket to remove it. (rusted/seized, what have you)

Then use a normal adjustable wrench or adjustable pliers to install the new one. (to not pinch the wire)...

Ya don't need the fancy socket with the slit...

 
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