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BMW 330 2002 - Exhaust flap not working #

Posted by Matthew Ladd on February 18, 2012, 6:20 pm

Year of Manufacture *: 2002
Engine Size and Code *: 3000

Hi there i have got a problem with the above car as the exhaust flap is not working.

it has had a genuine rear box fitted as the previous one stuck shutand corroded through.

i located the vacuum valve in the boot, started the engine and joined the two pipes together and the flap closed ruling out a vacuum leak. I then scoped the signal and there isnt one just battery voltage. im guessing there should be a pwm signal from ecu?

any suggested things to check would be much apreciated

thanks matt ladds

Re: BMW 330 exhaust flap not working

Posted by andyhyoung <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT5148' width='330' height='300' border=0 style='border:none;'> on February 18, 2012, 11:19 pm, in reply to "BMW 330 exhaust flap not working"

There is no mention of this flap on Bosch esi test or wiring.Perhaps it is just ignition controlled rather than pcm?
Have you tested the vac valve operation with a seperate power supply?

Re: BMW 330 exhaust flap not working

Posted by Matthew Ladd on February 19, 2012, 11:49 am, in reply to "Re: BMW 330 exhaust flap not working"
Message modified by board administrator February 20, 2012, 4:02 pm

i have also looked at a wiring diagram on tolerence and could not see anything to do with the exhaust flap, How-ever i am led to believe it must be pcm controlled due to the fact it opens and closes depending on throttle position and rev-range it could however have its own control box that i am un-aware of .

i have substituted the valve for a good known working egr vacuum valve similar in design but a bit bigger, it still plugged in and there was no change. I have nothing to supply it with a pwm signal so have not tried to power it up off the car

so does anyone no what controlls the exhaust flap on 330's?

thanks again

matt

Re: BMW 330 exhaust flap not working

Posted by andyhyoung <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT5148' width='330' height='300' border=0 style='border:none;'> on February 19, 2012, 12:02 pm, in reply to "Re: BMW 330 exhaust flap not working"
Andrew Young

As far as I can make out,the flap is vacuum controlled depending on the engine load.Idle ;high vac, reducing to low as engine load increases,thus the vacuum actuator/flap changes the exhaust flow path thro rear silencer.So what does the valve do?Not sure!

Re: BMW 330 exhaust flap not working

Posted by Lee Mackintosh <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT1348' width='330' height='300' border=0 style='border:none;'> on February 19, 2012, 12:59 pm, in reply to "Re: BMW 330 exhaust flap not working"
Lee Mackintosh

if you look under the garage management section then select technical info links, there is a heading for bmw wiring diagrams on there.

Select your model then look through each sub heading and you'll find some info relating to this system

I had a quick look but i could copy/paste it here. There isn't much info but a simple diagram of how its wired up.

Also a quick description on how it should work.

Re: BMW 330 exhaust flap not working

Posted by andyhyoung <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT5148' width='330' height='300' border=0 style='border:none;'> on February 19, 2012, 1:53 pm, in reply to "BMW 330 exhaust flap not working"
Andrew Young

Interesting read.The valve is dme controlled but one of the criteria is that the car has to be moving.(speed signal reqd)Perhaps this is why the system does not appear to function correctly.

Re: BMW 330 exhaust flap not working

Posted by Lee Mackintosh <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT1348' width='330' height='300' border=0 style='border:none;'> on February 19, 2012, 2:16 pm, in reply to "Re: BMW 330 exhaust flap not working"
Lee Mackintosh

Somewhere with in that wiring diagram there's a section that show a test screen but i can never get it to load up or function as it should.

Re: BMW 330 exhaust flap not working

Posted by matthew ladds <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=ukat3392' width='330' height='300' border=0 style='border:none;'> on February 19, 2012, 9:05 pm, in reply to "Re: BMW 330 exhaust flap not working"
Matthew Ladd

The owner informs me that he has bmw service data stating that it is simply a noise reduction/tuning device. On startup it should close the flap to give the back box more volume.

Regarding the speed signal im guessing it will open the flap at a pre determined speed.

A search on the bmw owners forums suggests the customer is right. It should close the flap on start up.

Re: BMW 330 exhaust flap not working

Posted by Steve Kefford <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT1094' width='330' height='300' border=0 style='border:none;'> on February 19, 2012, 10:01 pm, in reply to "Re: BMW 330 exhaust flap not working"

www.spagetticoder.org for wiring, TIS and parts.

Or http://wds.spaghetticoder.org/en/

http://wds.spaghetticoder.org/en/zinfo/HEL0498FB1214_M0AGK.htm

Cheers
Steve

Re: BMW 330 exhaust flap not working

Posted by Lee Mackintsoh <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT1348' width='330' height='300' border=0 style='border:none;'> on February 20, 2012, 8:12 am, in reply to "Re: BMW 330 exhaust flap not working"
Lee Mackintosh

i did a google search and came up with similar suggestions.

Seems different from the offical BMW data.

Re: BMW 330 exhaust flap not working

Posted by martin simonsohn <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=ukat3223' width='330' height='300' border=0 style='border:none;'> on February 20, 2012, 1:33 pm, in reply to "BMW 330 exhaust flap not working"
Martin Simonsohn

hi why dont you try and scope the output to the vac solonoid whilst driving with a vac guage first on the vac inline of feed and then inline
on the flap side just to confirm a good vac supply and then the solonoind operation
hth martin

Re: BMW 330 exhaust flap not working

Posted by Matthew Ladd on February 20, 2012, 7:20 pm, in reply to "Re: BMW 330 exhaust flap not working"
Message modified by board administrator February 23, 2012, 2:44 pm

I have ruled out vacuum as a problem by removing the pipes of the solenoid and joining the pipes together this closes the exhaust flap.

I have scoped the solenoid on both wires and have 13.9 volts on both wires with no pwm signal

There is no need to drive it as im told it should close when the car is started.

I think i'm going to call it a day on this one

The customer only brought it in because the old back box has corroded through

Spending a couple more hours labour diagnosing a fault that is only going to make his car a little quieter while idling is not top on his priorities but I said I would enquire on here on his behalf

thanks for the suggestions

Matthew ladds

Re: BMW 330 exhaust flap not working

Posted by Dave Hill <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT2783' width='330' height='300' border=0 style='border:none;'> on February 20, 2012, 8:49 pm, in reply to "Re: BMW 330 exhaust flap not working"

Interestingly enough the tail pipe flap can be actuated with GT1, but Autologic doesn't cover it!

"It is not one of our priorities, due to the simplicity of testing it via more conventional methods" was the explanation I was given when I raised the topic with Autologic.

To be fair, they are right.

I run one of these myself & this flap serves very little purpose in my opinion. the flap on my own car played up for a while. I played around with various things & came to the conclusion that it was best left permanently open.

Re: BMW 330 exhaust flap not working

Posted by Craig Hewison <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=ukat3409' width='330' height='300' border=0 style='border:none;'> on February 20, 2012, 10:25 pm, in reply to "Re: BMW 330 exhaust flap not working"
Craig Hewson

that doesn't sound like autologic they are normally 'no job too small' i can only speak about the C.R.A.P package tho as its the only one we run!

Craig

Re: BMW 330 exhaust flap not working

Posted by Dave Hill <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT2783' width='330' height='300' border=0 style='border:none;'> on February 23, 2012, 9:57 pm, in reply to "Re: BMW 330 exhaust flap not working"

Hi Craig.

>>that doesn't sound like autologic they are normally 'no job too small'<<

Yes I was a little surprised to see this omission from the activations menu. In fact I assumed that I was looking in the wrong place, which is why I rang them.

Autologic has many.. many strong points, but it has to be said that it is still a reverse engineered tool & as such, things are prioritised. If they don't consider a function "worthy" then they don't include it.

I would say though, that if you call them with a specific request on a particular subject, then you will find that they will do there utmost to help you with your predicament.

Often I find that features do not work as expected & I have to contact them to get things sorted. The fact that they bother to listen & usually respond within 24 hours, does bode well in their favour.

There is no such safety net with any dealer tool. Not that I am aware of anyway.

Re: BMW 330 2002 - Exhaust flap not working #

Posted by Colin Hedger <iframe src='https://members5.boardhost.com/ukautotalk4/info/user=UKAT1335' width='330' height='300' border=0 style='border:none;'> on February 26, 2012, 6:33 pm, in reply to "BMW 330 2002 - Exhaust flap not working #"
Colin Hedger

Hello Matthew,

The exhaust flap should remain closed at idle and open above 2500rpm when driven.
Constant vacuum is supplied to the exhaust flap solenoid in the boot which has a permanent +ve from fuse F3 (ign on). Above 2500rpm the solenoid gets a -ve supply from the engine ECU.
So at idle the ECU supplies no earth to the solenoid allowing vacuum to go through it directly to the exhaust flap closing it for quietness.
Above 2500rpm the ECU supplies -ve changing the solenoid position so that vacuum no longer goes to the exhaust flap and it springs open (for performance).
I think this is a common fault and I first noticed it on my wife's '02 E46 330i when it sounded a bit throaty on start-up. Investigation showed a permanent -ve supply from the ECU (not switching). I wasn't about to fit a new ECU so the solution? I wired in my own -ve supply to the solenoid through a rocker switch under the dash. Now when the wife drives it, it's quiet! When I drive it,I switch it over and it sounds a bit more sporty! - perfect, I don't know why BMW didn't do that in the first place!
It's clearly marked in the wiring diagram for E46 323i and 328i (same thing) in my Autodata Engine Management Systems book 9, page 122, item Y141 - should be in other Autodata diagrams.
If you type E46 exhaust flap into Google images, ther's a great picture and short description (bit small) about third row down.
Hope this helps you.

Colin

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