DIY BMW E46 Pre Cat Oxygen Sensor

[EddyKicksAss]

Did you say "Pre cat O2 spark plugs"? Nice :D

[waleedraza2007]

sir i have 318i 2004, my mechanic told me bank 1 sensor 1.. please tell me where it is located as that man said it's near exhasut pipe and here all scenario's kinda different..

thanks

[armandoOSU]

Hello. Getting ready to replace both my pre-cat o2 sensors. Question. Will the check engine light remove automatically once this is done?

[XionUnjust]

@armandoOSU Yes it will, but probably after some miles are put on or if you have a code reader.

[oscarv362370]

how much did the sensor cost?



[mitchrz1]

Hey,

I watched your video on changing of the O2 sensor - very good. But I need a recommendation from you.

Is it a good idea to replace all O2 sensors at the same time?

I was getting an error posting a link to the sensors that I'm going to get, but I'm guessing that I need two of each. Any additional information would be greatly appreciated. Thanks!

[XionUnjust]

@mitchrz1 Thank you.

When I got my first o2 code it was for the most front one, then a few months later the second one came. I would just replace all at once (not all four, but the same side either pre or post cat)

[mitchrz1]

@mitchrz1

Anyway the site is autoparts online canada (one word) dot com and if you go select bmw 325i and year as 2004, then select 325i sedan, then scroll down to the fuel injection category, those are the sensors I plan on picking up.

[oscarv362370]

Ok thanks, and how to know what sensor it is, if the scanner only tells me bank 1 and bank 2? doesnt tell me, bank 1 sensor 2,  do i have to change them all?? thanks again

[oscarv362370]

So if your looking at the car from the front, the two that are in in the left are pre-cat, sensor 1 is the front one, and sensor 2 is close to the firewall, post-cat are to the right and so on...?

[XionUnjust]

@oscarv362370 Correct

[oscarv362370]

To get this clear, whats all with this all bank 1 and 2 , sensor 1 and 2???? o.0?

Sorry for stupid questions jaja

[XionUnjust]

@oscarv362370 Bank 1 are the pre-cat sensors, what I change in this vid. Bank 2 are the post cat (under the car)

sensor 1 is the first in line and sensor 2 is the one right after

[oscarv362370]

How much was the sensors? And where did you buy them. I got p0141 and 71 how do i distinguish them? And is this the reason my car acts weird with the revs?? This are the only codes im getting, thanks again!?

[XionUnjust]

@oscarv362370 I think the cheapest to get the pre-cat Bosch sensors is on amazon.

For the lean codes, do this: take out your intake boots and look for any cracks, clean your MAF with CRC MAF cleaner and when you are low on gas put in one bottle of Chevron Techron fluid, 12 gallon, to your gas tank and fill up with premium. Also, the DISA unit (black box on the intake manifold) disconnect and if a ticking noise goes away replace that. The seal usually goes bad

[oscarv362370]

@XionUnjust thanks alot!!!! and by the way do you have the part number? I changed both of them, bought a disa a month ago, and the rest I might do it this weekend, and how do i reset the codes? I went to Autozone and the thing is that it won't let me reset.

[LuisJim81]

so i took out both my pre cat sensors, and i forgot witch one plugs into what. does bank 1 sensor 1 plug in to front of the engine?

[XionUnjust]

@LuisJim81 The connectors should be pretty much right over the sensor. Front most connector for the front sensor, etc.

[LuisJim81]

@XionUnjust thanks. i got all mixed up because i was installing headers and my labels came off, and the location of the sensors on the headers are way different.. thanks again.

[n3n3x3]

Oh oks... Any recomendations..!? Cuz i went to the dealer n we r talking abt 600 to change the sensors... Shuld i just change the firts one my selfs n let the dealer change the other one dat maybe save me some money... Or try to do bouth my selfs or just let the dealer have it !? :-(

[n3n3x3]

Yo.. Nice Work Man... So is the same For the one on the back??? Well ama give it a try... Lets hope i dont mess up my 325 bt still nice job...

[XionUnjust]

@n3n3x3 No, for the post cat they are hard to get to, you need a different tool and the wires go to the top center of the engine.

For these, they are easy.

[19army56]

Great work. I have a p0141 code. Heater circuit-bank 1 sensor 2. How do I locate it!

Thanks much

[XionUnjust]

@19army56 bank 1 are pre-cat. sensor 2 is the second one in the back (closer to the firewall)

[MilitaryMind354]

hello, what year is your e46?

[XionUnjust]

@MilitaryMind354 2002

[flskim906]

Good video. Would a bad o2 sensor cause fuel to be too lean? One day I was backing out of my garage and a code came up for "Fuel too lean bank 1", cleared the code and it ran fine. Really confused any help is much appreciated.

[XionUnjust]

@flskim906 If the O2 sensor was going most likely you would get a code for it. As for the fuel lean I would first check for any vacuum leaks to the throttle body body. Make sure the DISA (adjuster unit) is properly seated.

[flskim906]

@XionUnjust I am new to BMW seeing as how I had 2 Acura Integra's before this car.. how do you check if the DISA is properly sealed?

[BERGEN03]

Hello can you let me know Where the Bank 2 sensor 1 O2 sensor is located?

[jackeddemon]

where is the bank 2 sensor 2 O2 sensor? same place?

[XionUnjust]

@jackeddemon That should be after the cats, second sensor to the rear

[jackeddemon]

@XionUnjust sorry to bother you again, but i have looked at my car and online and i cannot find where that sensor is. do you have a diagram or something i could look at?

[BERGEN03]

Hello all I need to change the bank 2 sensor 1 O2 sensor is it on the same side of as what is reflected on the vid??

[darrenjb21]

The lost of power in my motor! Do u think this wil be from the 02 sensor as the Engine management light has come on! I have read that before changing the 02sensor check for cracks in the piping as this can mess u the reading to these sensors? Is this correct? But were do u check? Thanks. Darren

[darrenjb21]

The loss of power in my mo

[darrenjb21]

Hi I have 320 ci coupe and the issue is with lambda sensor? The car seems to be losing power i put it on the computer to diagnose the problem and it told me it's the lambda sensor! Is this video were u r replacing the 02 sensor the same thing? Regards Darren

[XionUnjust]

@darrenjb21 Yes, the lambda sensor is the oxygen sensor.

[ChevalierKadosh]

hi, where exactly is located the post and pre oxygen sensor ?

[XionUnjust]

@ChevalierKadosh Precat are the two that I'm doing. Post cat are accessible from under the car.

[ChevalierKadosh]

@XionUnjust cool thanks i though the one nearest to the passanger side was the post now i figure out there's 2 pre 2 post i know i suck

[dboucher26]

Where's the other pre cat O2 Sensor located? This video only shows one of them being removed.

[XionUnjust]

@dboucher26 right next to it, it's visible if you look down.

[dboucher26]

@XionUnjust Thanks, I found it. Correct me if I'm wrong but the pre-cat oxygen sensor's control the fuel to air mixture/ratio while the post-cat oxygen sensors monitor the catalytic converter's condition...

[XionUnjust]

@dboucher26 probably, I never really read that much about them. I had to change them regardless since i had codes for both. 

[veronica6010]

id appreciate your help thank you

[veronica6010]

my car is not starting, it starts but turns off right away? need help my email oscarvathotmaildotcom

[AlboBmw]

WIN

[2lowvdub]

Great videos! The video for the VCG replacement made the job much easier.

[bimmersgarage]

Excellent!

Thanks for the how-to.

[XionUnjust]

@bimmersgarage You're welcome