Exhaust Flap - Is there an app?

[MACK]

Hi,

Had a look at the exhaust flap on our 20i. I knew it wasn't closing at it should since we got it but had assumed this was either the flap sticking or someone had "golf tee" modded it. Well it turns out neither is the case. Long story short all the mechanical/vacuum bits are working. I'm getting a strong vacuum to the solenoid in the boot and a good live feed to it, but a weak earth. If you unplug the solenoid and power/earth it independently the exhaust valve is free moving, opening and closing as it should.
So the issue is the weak earth. My initial thought was I've got a wiring fault somewhere, but having now had a look at a wiring diagram for the solenoid it shows that the earth is controlled directly through the ECU. This got me thinking that it might not be a wiring fault at all and it might actually be the case that someone has turned the exhaust flap off with some sort of software. Does anyone know an app that does this on the E89. I've checked my Carly app and it doesn't do the exhaust flap, neither does ISTA D and my P is playing up! Does anyone know of another app that does on the E89?

Thanks

 

[MACK]

Hi,

Had a look at the exhaust flap on our 20i. I knew it wasn't closing at it should since we got it but had assumed this was either the flap sticking or someone had "golf tee" modded it. Well it turns out neither is the case. Long story short all the mechanical/vacuum bits are working. I'm getting a strong vacuum to the solenoid in the boot and a good live feed to it, but a weak earth. If you unplug the solenoid and power/earth it independently the exhaust valve is free moving, opening and closing as it should.
So the issue is the weak earth. My initial thought was I've got a wiring fault somewhere, but having now had a look at a wiring diagram for the solenoid it shows that the earth is controlled directly through the ECU. This got me thinking that it might not be a wiring fault at all and it might actually be the case that someone has turned the exhaust flap off with some sort of software. Does anyone know an app that does this on the E89. I've checked my Carly app and it doesn't do the exhaust flap, neither does ISTA D and my P is playing up! Does anyone know of another app that does on the E89?

Thanks

I've now seen a few threads on here and elsewhere of folks with exactly the same weak earth issue. I'm beginning to wonder if it is a fault with the ECU or the wiring after all :?

 

[Smartbear]

I disconnected the actuator on my 20i & prefer the slightly gruff exhaust note it gives
Rob

 

[ihadablackdog]

I disconnected the actuator on my 20i & prefer the slightly gruff exhaust note it gives
Rob

This ^

(I haven’t done it yet, but bought the end caps several months ago....must crack on and do it!).

 

[jllyons10]

I have Bimmercode app and have not discovered that option, at least for my car.

 

[enuff_zed]

I have the same issue as the OP. Flap always open.
To be honest, I quite like it like that so have never investigated further.

 

[MACK]

I have the same issue as the OP. Flap always open.
To be honest, I quite like it like that so have never investigated further.

I disconnected the actuator on my 20i & prefer the slightly gruff exhaust note it gives
Rob

Hi,

To be honest because I've not heard it on the road in its factory configuration I think I'm just curious and may well end up doing what you guys have and going back to the "golf tee mod" type configuration I've effectively currently got. My biggest gripe with it is just how loud it is on initial start up and first few minutes of running, especially with neighbours etc
I've being thinking about this whilst going stir crazy in the house. I may just wire up a switch and give it a trial run to see which way i prefer it. In deed if I like the switchability I may permanently install a switch in the arm rest etc. Did that with a Boxster with the PSE years back and it worked a treat.

enuff_zed your's is yet another with this issue. I'm beginning to think its a common fault, they can't all have been turned off in the software. Then again I'm also not really sure how many folks are checking that no one has done the "golf tee mod" or unplugged the solenoid previous to their ownership

 

[MACK]

I have Bimmercode app and have not discovered that option, at least for my car.

Thanks for confirming that. Another one off the list

 

[enuff_zed]

I have the same issue as the OP. Flap always open.
To be honest, I quite like it like that so have never investigated further.

I disconnected the actuator on my 20i & prefer the slightly gruff exhaust note it gives
Rob

Hi,

To be honest because I've not heard it on the road in its factory configuration I think I'm just curious and may well end up doing what you guys have and going back to the "golf tee mod" type configuration I've effectively currently got. My biggest gripe with it is just how loud it is on initial start up and first few minutes of running, especially with neighbours etc
I've being thinking about this whilst going stir crazy in the house. I may just wire up a switch and give it a trial run to see which way i prefer it. In deed if I like the switchability I may permanently install a switch in the arm rest etc. Did that with a Boxster with the PSE years back and it worked a treat.

enuff_zed your's is yet another with this issue. I'm beginning to think its a common fault, they can't all have been turned off in the software.

I agree with what you say regarding the start up noise. My garage is set slightly to the rear of my house. When I back the car out I have to carefully negotiate a narrow car port between my house wall and the bungalow next door. Their bedroom is against this wall, so when we wake up early at the weekend and decide a bacon butty on the coast will do for breakfast (pre-virus of course :wink: ) then I do wonder how the sound reverberates through their wall at 7am on a Sunday.
However, as these new neighbours seem to think a small town in deepest Norfolk means it is ok to light a bonfire whenever they like, usually on a sunny day when everyone is sitting out in their gardens; and then to add to that, have re-homed two rescue dogs who yap incessantly if I so much as fart in my own living room; well if my foot slips a little on the throttle every now and then, I'm not quite so concerned.

Yes, we have spoken to them. No it made no difference.

 

[ihadablackdog]

Quick question that I might have asked in the past but my single brain cell can’t remember!

What is the point of the flap? I know it moves and affect sound etc and is open In certain conditions, but why?

 

[MACK]

Quick question that I might have asked in the past but my single brain cell can’t remember!

What is the point of the flap? I know it moves and affect sound etc and is open In certain conditions, but why?

My understanding is its all about noise, doesn't affect bhp/torque, although some seem to dispute that. It simply makes the car a bit quieter at low revs when it should be closed and opens at circa 3,500rpm. So a bit quieter around town or cruising on the motorway, a bit more raucous when on the beans!

 

[Smartbear]

Yep, noise testing on new vehicles takes place at specific rpm/load criteria, i bet the exhaust flap’s designed to be closed at these exact moments to assist in obtaining low decibel readings.
The n20 sounds a bit raspy on cold start up due to an air pump operating to clean up the extra rich exhaust gases (it dilutes them i believe)
Rob

 

[MACK]

Yep, noise testing on new vehicles takes place at specific rpm/load criteria, i bet the exhaust flap’s designed to be closed at these exact moments to assist in obtaining low decibel readings.
The n20 sounds a bit raspy on cold start up due to an air pump operating to clean up the extra rich exhaust gases (it dilutes them i believe)
Rob

That's an interesting point Rob regarding the air pump, thinking about it I think I've seen a post of yours about that before. I guess I'm just curious to hear the difference between the air pump and open the valve on start up (what I've currently got) and air pump but closed valve (what I should have) and how much quieter the closed valve really is on a motorway etc.

 

[Player 1]

Just a thought, you could take a spare fuse slot in the fuse box, run a few wires to the solenoid and a switch in the cabin (down where the blanked off boot release is maybe) then have it manually switchable to loud and quiet?

 

[Anonymous]

Yep, noise testing on new vehicles takes place at specific rpm/load criteria, i bet the exhaust flap’s designed to be closed at these exact moments to assist in obtaining low decibel readings.
The n20 sounds a bit raspy on cold start up due to an air pump operating to clean up the extra rich exhaust gases (it dilutes them i believe)
Rob

SmartBear according to the N20 technical training manual dated 2010 the noise you hear is the vacuum pump providing brake servo / waste gate control / exhaust flap control in that order power.

There is no injection / admission of air post exhaust port..

 

[Smartbear]

Yep, noise testing on new vehicles takes place at specific rpm/load criteria, i bet the exhaust flap’s designed to be closed at these exact moments to assist in obtaining low decibel readings.
The n20 sounds a bit raspy on cold start up due to an air pump operating to clean up the extra rich exhaust gases (it dilutes them i believe)
Rob

SmartBear according to the N20 technical training manual dated 2010 the noise you hear is the vacuum pump providing brake servo / waste gate control / exhaust flap control in that order power.

There is no injection / admission of air post exhaust port..

That’s surprised me, the brake servo requires vacuum assistance permanently in order to work as does the exhaust flap.
lci cars have solonoid controlled wastegates which are electronic, but the other items would need the vacuum pump running constantly so why is the raspy/blowing sound only evident on cold start-up? It does sound as though it emanates from around the turbo area :?
Rob

 

[Anonymous]

Yep, noise testing on new vehicles takes place at specific rpm/load criteria, i bet the exhaust flap’s designed to be closed at these exact moments to assist in obtaining low decibel readings.
The n20 sounds a bit raspy on cold start up due to an air pump operating to clean up the extra rich exhaust gases (it dilutes them i believe)
Rob

SmartBear according to the N20 technical training manual dated 2010 the noise you hear is the vacuum pump providing brake servo / waste gate control / exhaust flap control in that order power.

There is no injection / admission of air post exhaust port..

That’s surprised me, the brake servo requires vacuum assistance permanently in order to work as does the exhaust flap.
lci cars have solonoid controlled wastegates which are electronic, but the other items would need the vacuum pump running constantly so why is the raspy/blowing sound only evident on cold start-up? It does sound as though it emanates from around the turbo area :?
Rob

Dear Concerned..Correct, True, Pass, Maybe

 

[Smartbear]

SmartBear according to the N20 technical training manual dated 2010 the noise you hear is the vacuum pump providing brake servo / waste gate control / exhaust flap control in that order power.

There is no injection / admission of air post exhaust port..

That’s surprised me, the brake servo requires vacuum assistance permanently in order to work as does the exhaust flap.
lci cars have solonoid controlled wastegates which are electronic, but the other items would need the vacuum pump running constantly so why is the raspy/blowing sound only evident on cold start-up? It does sound as though it emanates from around the turbo area :?
Rob

Dear Concerned..Correct, True, Pass, Maybe

I get all that (except my model doesn’t have a vacuum powered wastegate)
So why is it so loud on initial cold start? Does the pump work extra hard to prime the reservoir i wonder?
Rob

 

[MACK]

Just a thought, you could take a spare fuse slot in the fuse box, run a few wires to the solenoid and a switch in the cabin (down where the blanked off boot release is maybe) then have it manually switchable to loud and quiet?

I was thinking along similar lines although i'm probably just going to use the existing live feed (which is working fine) to the solenoid and just rig a switch up for the earth side. I was thinking or putting it between my cup holders in the arm rest, but I'm just going to try it all temporarily before a permanent install

 

[Smartbear]

Just a thought, you could take a spare fuse slot in the fuse box, run a few wires to the solenoid and a switch in the cabin (down where the blanked off boot release is maybe) then have it manually switchable to loud and quiet?

I was thinking along similar lines although i'm probably just going to use the existing live feed (which is working fine) to the solenoid and just rig a switch up for the earth side. I was thinking or putting it between my cup holders in the arm rest, but I'm just going to try it all temporarily before a permanent install

I’m wondering if that might flag up a fault code? :?
Rob