O2 Sensor replacement. Pre-Cat

[MP5 Kyle]

Hey everyone, i was told by my mechanic that my rear?? Pre-cat O2 sensor needed to be replaced. I was wondering what O2 sensor that would be, I'll attach a pic of what i think it might be but if anyone has pics of which one it actually is if im wrong please post it. or if you can let me know which one it is.

What one I think it is.

Thanks in advance for all the help!

Kyle.

 

[CTt3P5]

Nope that is your main. Look under the car and you will find the secondary.

 

[MP5 Kyle]

whereabouts would it be? and how many are there lol. sorry for all my questions im not really a wrencher and im also only 16
Also, thanks for the really quick response

 

[bigpturgeon]

The one your looking for is after the cat. just go underneath the engine and you will see it

 

[CTt3P5]

What he said....there are two. Get under the car from the front and you will see it just after the pre-cat on the downpipe.

 

[bigpturgeon]

here is a visual.. (breakn)

 

[MP5 Kyle]

thank you everyone so much. time to buy one and get it installed. my stupid car has been richening up the fuel and im spending like 70$ a week on gas and im only commuting to school about 32kms each way.

 

[bigpturgeon]

save your self some coin and do it yourself its easy all you need is a wrench

 

[MP5 Kyle]

really? is there any guides?

 

[goodfornothing]

Depends if you get a universal or one specific for our cars.

If you get the protege5 replacement it's a little more expensive, but it's plug and play. Unplug the wire, unscrew with a wrench, install the new one in reverse order. If it's a universal type, you'll have to splice the wires with the old plug.

 

[bigpturgeon]

(breakn) Just get a BOSCH there reliable they work nuff said just follow what goodfornothing said. The universal will work and its cheaper but if your no good with wiring stuff then get the one specifically for the car. remember you want a down-stream sensor since it is after your cat. This really is like a 10 min job its easy enough for you to do your self they cost allot to begin with don't spend more bringing it to a mechanic to charge you more money. here is an example of what you want http://www.autozone.com/autozone/pa...earch&itemIdentifier=491422_102074_1784_98000

 

[MP5 Kyle]

Thanks guys. I want to get the one that you sent me but i cant check the pricing for it because its only for the states apparently -.- but its nice to know what i need now, so i can find one. Also, thanks again for the help!

Kyle

 

[droplet]

Replaced this with Denso Part # 2344752 (downstream O2 sensor) back in October last year:

http://www.rockauto.com/catalog/moreinfo.php?pk=991609

So far so good, the CEL is gone (forgot the code). Takes a few minutes to do.

 

[MP5 Kyle]

thank you, will be purchasing that one tonight!

 

[larson701]

If you do try to install the O2 sensor yourself, purchase the tool to do this also. The tool looks like socket with a slot to fit the wiring thru. There may not be enough room or an angle to fit a box-end or open-end wrench onto the sensor.

Good luck!

 

[slavrenz]

thank you everyone so much. time to buy one and get it installed. my stupid car has been richening up the fuel and im spending like 70$ a week on gas and im only commuting to school about 32kms each way.

Well, I hate to be the bearer of bad news, but replacing the rear O2 sensor will have zero effect on your fuel usage - it is only there to monitor the cleaning ability of your catalytic converter. The front O2 sensor (closer to the engine) is what actually helps regulate your air/fuel ratio - are you sure this isn't the one that went bad?

 

[MP5 Kyle]

well i was told its the rear, but itll probs be both of em with my luck! its ok, if its the front then ill have 2 new O2 sensors aha. i ordered the other one this morning so theres no going back now!

Thanks for bearing that bad news though, some always has to... haha

 

[pureform]

Resurrecting this thread cuz I have a few questions regarding the (front/upper/pre cat) heated O2 sensor. My PR5 threw the p0031 code (Heated Oxygen Sensor Bank 1 Sensor 1 heater circuit low) a couple days ago. I am about to pick up a new sensor and had a few questions regarding removal/installation. First off, does the exhaust manifold heat shield have to be removed to get to the HO2 sensor..I have seen there are special Oxygen Sensor sockets for removal, but was wondering what is the easiest/most cost effective way to get the sensor replaced on my own. Any advice from someone experienced with this procedure for the protege5 would be greatly appreciated! thanks

 

[RABID_MP5]

yeah +1 on the primary for running rich. On pulling the old ones, you might have to just cut the wires and use like a deep well impact socket to apply the torque required. I've had problems with the slotted type actually jumping. You're gonna pitch it anyway...

 

[i12drivemyMP5]

Resurrecting this thread cuz I have a few questions regarding the (front/upper/pre cat) heated O2 sensor. My PR5 threw the p0031 code (Heated Oxygen Sensor Bank 1 Sensor 1 heater circuit low) a couple days ago. I am about to pick up a new sensor and had a few questions regarding removal/installation. First off, does the exhaust manifold heat shield have to be removed to get to the HO2 sensor..I have seen there are special Oxygen Sensor sockets for removal, but was wondering what is the easiest/most cost effective way to get the sensor replaced on my own. Any advice from someone experienced with this procedure for the protege5 would be greatly appreciated! thanks

First try cleaning the soot off it. I have had this code a couple of different times at long intervals between them and just cleaned the soot off the sensor with spray can of carb cleaner. Has worked both times and still running the original o2 sensors and getting 31mpg out of a sportauto. They are still working. The downstream one is the one that was causing code both times.