Anzafin

It's a pre-cat O2 sensor.

- Antti -

Anzafin

May 19, 2013

The following happened earlier this week...

And the issue this time was the little scratches/chips in right corner of the rear bumper. I caused them myself on Monday when I backed up to my neighbour's wheelbarrow :grrrr:.
I decided to try to fix them myself, using color coded paint and some other stuff. I haven't done this kind of jobs before, so there was some trials and errors included.


This is what I did:

1) Investigating the damage (and some cursing).



2) Rubbing the damaged area with Menzerna PF2500 + piece of LC CCS yellow cutting pad --> With this I wanted to see if the chip areas could be cleaned a bit. There was some "rolled" paint on the edges of the holes and I got rid of it.


3) Now they were nice and clean for the next steps.


4) Paint.


5) Filling up the holes. I put a thin layer and let it dry and so on.


6) Here I did an error. I left the halogen too close to the car and the heat caused some bubbling in painted spots.


7) On next day I did the first wet sand with a 2500 grit paper + soap water.


8) The bubbles in paint left so deep tiny holes in painted areas that I had to put some paint again to cover them.


9) Then, on the next day I did the wet sanding again and followed it with a DA polisher + Menzerna SF4500 + LC CCS White Polishing Pad combination.

10) After these efforts I'm pretty satisfied with it.


- Antti -

Anzafin

May 21, 2013

All right, the story goes on.

Today I changed the right side pre-cat O2 sensor.
I took some pictures and maybe this could be used as a DIY.

Here is how it happened.


Starting point in INPA.


Here's the Bosch's sensor (Bosch 17051), which is exactly the same as from BMW (Part #11787836394), except cheaper. I ordered this from Germany and it was 135€.


Then, lets get dirty. Removing the underfloor coating. It is attached with about 100000 screws (8mm).


Removing the protective plate (16mm).


Next I opened two screws (8mm) of the steering gear cover (part 01) on the outer side to get some room for the wrench. So I didn't remove it completely. These screws are true fun to reach btw.


One little piece of heat cover has to be removed to get the sensor cord visible. It was attached with one screw (8mm) and one nut (10mm).


Here you can see the sensor plug and the cord. The sensor itself locates in front of the cat.


And here the 22mm socket of the sensor can be seen (blue). The sensor is removed with a 22mm open-end wrench, but you don't have much room to play with it lol! The plug (green) is removed by pulling it to right and then unattaching it from the wires of the car.


New vs. old.


To protect the cord while screwing the new sensor in, I bound it with a zip-tie. I cut it off when I had installed the sensor in.


Then, after putting everything back in reverse order, I started INPA, cleared the error and then read some data to make sure the sensor works properly. Done .



Thank you for watching!

- Antti -

west

That paint repair looks great. Nice work!

Quarta2six

The only water you used was from a spray bottle nothing with a steady stream? N what did you cover the alternator with?

Anzafin

You're talking about the underhood cleaning right?
Yes, I used only a spray bottle. I didn't cover the alternator or anything else either. I didn't let the water run down to the sensitive parts.

- Antti -

MoOriginal

As usual Antti

A fantastic detailed post !

Anzafin

Thanks!

Quarta2six

Yes, thats some great work Im going to try this. I thought I needed a steady stream of water never thought to use a spray bottle.

dens310

All i can say bmw should pay you for your knowledge.How I wish your in so-california. hands down to you sir.