E46 M3: EVAP (Charcoal Canister) Delete DIY

Well, it's a bit crappy, but you should get the idea.

What you will need:
1) 2 oil filters with a 3/8" dia
2) 3/8" dia hose, 15-30 inches (depending on how many loops you want)
3) 3/4" clamps, or anything that can go down to that size
4) zip ties

I started by figuring out which vent pipes vented out/in and then attached one way filters according to the direction the air flows.

I attached the filters to the 3/8" dia hose, clamped them on. the vent pipe that pulls air in, was the shorter hose and the vent pipe that pushes air out was a bit longer, so I was able to loop it once. I've read you should loop it a couple times and that it doesn't even matter; so I just did one loop.

I slid the 3/8" dia hose (3/4" outter dia) into the vent pipes, after I trimmed them. Really doesn't matter where, I cut mine so it was right behind the lower wheel well area. Clamp them down, should already be a tight fit. I zip tied the hoes/filters to the lower exterior of the batter box.

And lastly.... I then used a vacuum plug/cover to plug the blue line that goes to the airbox.

Total drop was 8 lbs, I still need to pull the evap mount off, I'm expecting another 5 or so lbs with that - as it's all steel.

Sorry I didn't get more pics, I was figuring it all out as I went along, so I only took a few at the end. If you want more pics or better angles, let me know an I can take some.

Pics:
My loop is seen here. I zip tied the top of the look to the upper battery box area.


At the top of the picture you can see the blue return line, just plugged it and zip tied it for a little extra security.


Here you can kind of see how the filters are inserted opposite of each other.

Great thread, I'd like to see more pics, I'm having a hard visualizing all you did under there...

Sorry about that, but I don't really have more pics right now. I can take some in a couple days.

Basically, you're looking for the inside of the right rear tire in the first pic. The hoses are coming out of the lower right side of the gas tank.

I'll try to take more pics.

On a side note, everything is running fine, no loss in MPG or fuel; and not any added MPG. I did pull the hose off from the front and also took out the EVAP sensor thing out, then plugged it up. Kinda hard to explain and of course I didn't take any pics of that part.

I'll take some pics from under there and you can guide me!

We can do that, too. Just PM whenever you have the pics.

Pardon my stupidity, but what's the benefit of this bypass? Besides the minimal weight reduction? Won't the ECU throw a code? Given that it's part of the emissions control system, iirc.

Also, does this only apply to the M3?

Originally Posted by FM3T10

Pardon my stupidity, but what's the benefit of this bypass? Besides the minimal weight reduction? Won't the ECU throw a code? Given that it's part of the emissions control system, iirc.

Also, does this only apply to the M3?

Weight loss is the only benefit and other than the code it will not hurt anything. I had already deleted my SAP, so there wasn't a point in keeping this either.

After reading your description a few times I think I understand what needs to happen.

Why does the line need to be looped?

The reason for looping is to prevent a siphon if enough fuel sloshed up into the hose or possibly if you rolled the car.

Just a note though, only one of the lines that connects to the charcoal canister actually needs to be filtered. One of them connects to the expansion tank and the other is just an exhaust line that is open behind the fender liner.

You can see here that only line 3 connects to the expansion tank.

I just looked under there and I see that Line 15 is just a vent tube that comes out from the EVAP container. That being said I'm guessing that there is nothing that needs to be done with that line?

Ok, so it looks like to just loop the line #3 a few times and I'm set.

WHich direction do I point the filter, flow outwards towards the atmosphere or flow inwards?

Originally Posted by JTRM3

WHich direction do I point the filter, flow outwards towards the atmosphere or flow inwards?

When fuel is consumed from the tank it will create a vacuum on the vent line.