Foot trunk release not working M Performance and other rear diffusers

[DanMpower]

Originally Posted by rhk118

Got the trunk kick sensor to work reliably with BMW CF diffuser.

I have the BMW rear diffuser and just did the modification above except zip tied it a bit higher so nothing is visible. I noticed like the original post of this thread says if the 2 middle install screws are used to stabilize the diffuser to the muffler heat shield then the kick function doesn't work, take the screws out and all of a sudden it works flawlessly. I think the screws are grounding the diffuser to the heat shield or messing with some gaussian distribution/flux capacitor in the kick sensor (insert clearly not an engineer quip here) and it doesn't work. I tried inserting rubber and plastic spacers between the diffuser and the heat shield but the metal screw would still prevent opening. So...I zip-tied the center diffuser tabs to the heat shield (2 each) rather than using the screws and kick function 100% active. For the 1 time a year I will actually need it!

Found this to be exactly how mine behaved after the MP rear diffuser. Instead of using zip ties though, I bought some plastic push clips and now my kick function works 100 percent with the MP diffuser.

[jmr0311]

Lloyd, can you share which kind of plastic push clips you bought for your rear diffuser installation? I used the good all zip tie but wouldn't mind using a clip for better support.

[SherM4n]

Originally Posted by dinonz

The BMW installation instructions say to deactivate the kick feature because of this.

Not doubting (and I realize I'm quoting a 2-year old post), but what instructions are you using? The pdf posted here doesn't seem to mention this. Thanks!

Edit: Never mind, found an updated pdf that does indicate to disable the trunk kick access here.

[Ed_rx7]

mine has the carbon diffuser already... does the kick function only come with comfort access cars?

[sandwi54]

Originally Posted by Ed_rx7

mine has the carbon diffuser already... does the kick function only come with comfort access cars?

Yes the kick function is part of the comfort access option. If you have a 2015 model and didn't get the executive package, you don't have comfort access.

[Penguinman87]

Originally Posted by LloydChristmas

Found this to be exactly how mine behaved after the MP rear diffuser. Instead of using zip ties though, I bought some plastic push clips and now my kick function works 100 percent with the MP diffuser.

Does your foot have to touch the diffuser in order for it to work 100% of the time or does it function exactly as stock diffuser does?

Thanks

[sandjam]

Originally Posted by Status Gruppe MNF

Trunk feature works 100% with our pre-preg CF Finned diffuser

I have had your diffuser for 2 years and its hit or miss, mostly never works when I want it to.

I am doing it exactly as your video shows in case your are wondering.

So I would not claim 100%.

[TheONE24]

I bought my F82 used and it already had a full wrap around diffuser in the rear. Not sure what brand it is. I was lucky to get the trunk kick to work every now and then and it would open constantly when washing my car with the key in my pocket. I read on one of the threads somewhere that someone had success removing the two plastic push rivets from the top sensor and unhooking the two middle clips from the bottom sensor. I did this today, which in effect causes the sensors to hang down lower, and so far it is working great. Since it was today I'm curious if in the future I get false openings when driving in the rain etc.. If I do I will update the post but so far this seems to be the easiest fix I've seen. Hopefully this helps out.

[SD ///M4]

Originally Posted by TheONE24

I bought my F82 used and it already had a full wrap around diffuser in the rear. Not sure what brand it is. I was lucky to get the trunk kick to work every now and then and it would open constantly when washing my car with the key in my pocket. I read on one of the threads somewhere that someone had success removing the two plastic push rivets from the top sensor and unhooking the two middle clips from the bottom sensor. I did this today, which in effect causes the sensors to hang down lower, and so far it is working great. Since it was today I'm curious if in the future I get false openings when driving in the rain etc.. If I do I will update the post but so far this seems to be the easiest fix I've seen. Hopefully this helps out.

Since your key fob is nowhere near the trunk while you're driving, there's no way that this will happen. It's just not the way it works.

[Alan l.]

Originally Posted by RAETD M

Found this to be exactly how mine behaved after the MP rear diffuser. Instead of using zip ties though, I bought some plastic push clips and now my kick function works 100 percent with the MP diffuser.

This^^

I used plastic push pins similar to what holds your interior trunk panels that I got from amazon and this feature works every single time with my oem MP diffuser.

[mpower3o2]

Originally Posted by Alan l.

This^^

I used plastic push pins similar to what holds your interior trunk panels that I got from amazon and this feature works every single time with my oem MP diffuser.

Have a link to these push pins?

[Alan l.]

I bought this kit

https://smile.amazon.com/gp/product/...?ie=UTF8&psc=1

[ProfM3]

I have a M performance carbon diffuser on my car and was experiencing the problem of the kick to open function not working correctly. It was not just that it didn't work when you wanted to use it but it would trigger seemingly randomly. The other night my foot brushed underneath the rear driver's side corner of the car and the trunk popped open. Other times I would find the trunk had opened unexpectedly.

On my car the 8mm screws for the 2 tabs in the center of diffuser go through the diffuser, then the heat shield, then the plastic part underneath that holds the screw clip that engages the 8mm screw.

Based on the comments in this thread that there is an electrical connection between the diffuser and the heat shield because they are in contact with each other, put a rubber spacer between the diffuser tab and the heat shield. I also used a couple of plastic fasteners rather than the 2 metal screws (which would also provide a conductive path between the diffuser and the heat shield.

After doing this the trunk kick to open function started working reliably with the BMW M Performance carbon fiber diffuser. Hopefully it will remain working, otherwise I will code out the function. I like the diffuser more than I need the foot kick to open trunk release function.

Here's a photo of the parts I used.

[torvektheo]

Originally Posted by ProfM3

I have a M performance carbon diffuser on my car and was experiencing the problem of the kick to open function not working correctly. It was not just that it didn't work when you wanted to use it but it would trigger seemingly randomly. The other night my foot brushed underneath the rear driver's side corner of the car and the trunk popped open. Other times I would find the trunk had opened unexpectedly.

On my car the 8mm screws for the 2 tabs in the center of diffuser go through the diffuser, then the heat shield, then the plastic part underneath that holds the screw clip that engages the 8mm screw.

Based on the comments in this thread that there is an electrical connection between the diffuser and the heat shield because they are in contact with each other, put a rubber spacer between the diffuser tab and the heat shield. I also used a couple of plastic fasteners rather than the 2 metal screws (which would also provide a conductive path between the diffuser and the heat shield.

After doing this the trunk kick to open function started working reliably with the BMW M Performance carbon fiber diffuser. Hopefully it will remain working, otherwise I will code out the function. I like the diffuser more than I need the foot kick to open trunk release function.

Here's a photo of the parts I used.

Where did you get the plastic fastener screw and the rubber grommet? Thanks for sharing the tips

[ProfM3]

Originally Posted by torvektheo

Where did you get the plastic fastener screw and the rubber grommet? Thanks for sharing the tips

Originally Posted by torvektheo

Where did you get the plastic fastener screw and the rubber grommet? Thanks for sharing the tips

You can get the plastics fasteners from a BMW dealer or even Amazon:

https://www.amazon.com/dp/B07CJHR26Q..._a-P2Eb0DTBR9Q

(8mm expanding rivet BMW part 51471911992)

The grommets can found at a regular hardware store.

[fabulousprofound]

I just had a diffuser installed today at a shop and they would not do this trunk kick fix for me. They said I run the risk of the sensor melting because relocating it makes it so close to the exhaust heat shield, and they wanted no liability. Has anyone had issues with theirs melting or failing from doing this mod?

[torvektheo]

Originally Posted by fabulousprofound

I just had a diffuser installed today at a shop and they would not do this trunk kick fix for me. They said I run the risk of the sensor melting because relocating it makes it so close to the exhaust heat shield, and they wanted no liability. Has anyone had issues with theirs melting or failing from doing this mod?

Apply this fix. I made a video of the fix that worked for me and many other guys from the forum. Thanks


https://www.bimmerpost.com/forums/sh...php?p=26252513

[-nexus-]

Originally Posted by torvektheo

Apply this fix. I made a video of the fix that worked for me and many other guys from the forum. Thanks


https://www.bimmerpost.com/forums/sh...php?p=26252513

+1 that this works.

I installed my CF diffuser using plastic clips for the two middle screws and the boot kick works 100% of the time. No sensor relocation or anything messy, just plastic clips as shown in the video. 1500km later and no issues.