335i - Emissions Warning Light

NFS · 03-12-2010, 01:36 PM

Yellow emissions warning light came on this week. Took it to dealer as recommended in the manual and they found a 'lean mixture' fault code. They checked the microfilter and pipes, found no problems, reset the warning, test drove the car and found the light stayed off.

I took the car back and did around 200 miles. Light came back on later that evening. This time the dealer did not find a fault code. This seemed to interest them as the light was still very much on. They have been determined to keep the car for investigations. They still haven't found anything after 48 hours, but want to do more tests with 'technical support' from BMW UK.

I've asked them to reset the light (which is staying off for now) and have taken the car back as this approach seems wrong to me (and frankly I want my car back if it isn't broken). Having searched on the forum I've found a few posts on this, suggesting that it can be fairly common. Some people saying it happens if the fuel filler cap is not on tight?

If I were being cynical, I might suspect that the service manager is happy to keep my car on site indefinitely whilst charging BMW for all sorts of tests etc.

Would be grateful for some advice from the experts.

F104 · 03-12-2010, 01:55 PM

I got myself the Bavarian Technic cable and software from the US. One of its functions is to read out /erase fault codes (both shown, and not shown). It won't give the answer to your question, but will show what faultcodes the car has seen. And then it can do a whole lot more.

a1reader · 03-12-2010, 01:59 PM

It is quite worrying that warning lights are coming up on a very new 335i that to my knowledge hasn't even been tuned (yet

). Do let us know how the dealer gets on with your car. I'll watch this with interest.

NFS · 03-12-2010, 02:01 PM

I've searched and found this thread, which tends to suggest that this may not be a massive issue:

http://www.e90post.com/forums/showth...ons+light+335i

Anyone ever heard of the emissions light being on, with no fault code?

Sounds really odd to me.

TMP · 03-12-2010, 03:07 PM

Quote:

Originally Posted by NFS

I've searched and found this thread, which tends to suggest that this may not be a massive issue:

http://www.e90post.com/forums/showth...ons+light+335i

Anyone ever heard of the emissions light being on, with no fault code?

Sounds really odd to me.

Interesting old post - may be worth a PM to see if this he did get this fixed on his 335i?

So if there isnt an actual fault with the engine, then I guess there is a fault with the warning light coming on for no reason

understand why you dont want to leave it with the stealer though.....rock and hard place spring to mind.

zltm089 · 03-12-2010, 04:09 PM

I'm no expert....but I believe, the mechanic did mention about "lean mixture/ or fuel mixture" something when I was having problems with my one....its was just a big lump of everything....software update, solenoid valve, fuel mixture, injectors, carbon, cylinder heads....all these "technical" words were mentioned to me.....I just didn't have a clue!...

I can look for email communications between me and the Workshop Manager if thats gona help? In my experience, engine warning lights or emission lights are not a good sign on a 335i....

fingers crossed in ur case ...its not major...

NFS · 03-13-2010, 07:58 AM

Light was off this morning and stayed off during a 20 mile drive. Car was parked for about 2 hours. Then the light came on as I set off for home, within about 5 minutes of starting the car. Stayed on all the way back. Engine is running fine, with no loss of power

Am at a loss as to what to do next.

I suppose I will ask the dealer to check for error codes on Monday and try to get them to explain everything they have checked so far.

Essentially after having the car for 36 hours, they have found nothing wrong with it, other than the warning light coming on. So frustrating. I need it all of next week and am not in the mood to hand it over to them again if they have no clue what is wrong.

dxb335d · 03-13-2010, 08:16 AM

Simon, how old is your car?!

NFS · 03-13-2010, 08:22 AM

Quote:

Originally Posted by dxb335d

Simon, how old is your car?!

Brand new Carl. Built Dec 2009. Done 2500 miles.

dxb335d · 03-13-2010, 08:47 AM

Registered Jan/feb?

Hope it gets sorted soon mate!

NFS · 03-13-2010, 09:36 AM

Quote:

Originally Posted by dxb335d

Registered Jan/feb?

Hope it gets sorted soon mate!

Was registered Mid Dec, so coming up to 3 months old now. Still think of it as brand new though.

Serjames · 03-15-2010, 07:18 PM

I would bet a dollar to a dime this is a fault with the Lambda probes.

I have a spare set you can borrow if you wish to test them.. ?
The code will appear if it doesn't read a "catalysed" exhaust mixture, i.e. decatted down pipes without "mod" etc.

Might be worth doing a Manual Labda probe test and getting the ACTUAL versus the displayed results. Tony's Bavarian kit could do this, or so could Birds I would imagine.

It could be a damaged Catalyser - not cleaning the exhaust up enough, or perhaps a short leading to a miss-reading on the probe. You really need to get a proper independent Lambda reading from an MOT / Dyno place I think to eliminate an ACTUAL Air fuel issue.

let me know about the Lambda cables, (cost me £125 and they're sitting in a box !)

SJ

03-12-2010, 01:36 PM	#1
NFS Major General 275 Rep 9,218 Posts Drives: M340i Join Date: Jul 2006 Location: UK iTrader: (0)	335i - Emissions Warning Light - Help Please! Yellow emissions warning light came on this week. Took it to dealer as recommended in the manual and they found a 'lean mixture' fault code. They checked the microfilter and pipes, found no problems, reset the warning, test drove the car and found the light stayed off. I took the car back and did around 200 miles. Light came back on later that evening. This time the dealer did not find a fault code. This seemed to interest them as the light was still very much on. They have been determined to keep the car for investigations. They still haven't found anything after 48 hours, but want to do more tests with 'technical support' from BMW UK. I've asked them to reset the light (which is staying off for now) and have taken the car back as this approach seems wrong to me (and frankly I want my car back if it isn't broken). Having searched on the forum I've found a few posts on this, suggesting that it can be fairly common. Some people saying it happens if the fuel filler cap is not on tight? If I were being cynical, I might suspect that the service manager is happy to keep my car on site indefinitely whilst charging BMW for all sorts of tests etc. Would be grateful for some advice from the experts.
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03-12-2010, 01:55 PM	#2
F104 Captain 19 Rep 732 Posts Drives: E92 320D M-sport Join Date: Apr 2008 Location: belgium iTrader: (0)	I got myself the Bavarian Technic cable and software from the US. One of its functions is to read out /erase fault codes (both shown, and not shown). It won't give the answer to your question, but will show what faultcodes the car has seen. And then it can do a whole lot more.
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03-12-2010, 01:59 PM	#3
a1reader Evolve tuned... 9 Rep 291 Posts Drives: E93 335i M-Sport Join Date: Aug 2009 Location: Wilts, England iTrader: (-1)	It is quite worrying that warning lights are coming up on a very new 335i that to my knowledge hasn't even been tuned (yet ). Do let us know how the dealer gets on with your car. I'll watch this with interest.
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03-12-2010, 02:01 PM	#4
NFS Major General 275 Rep 9,218 Posts Drives: M340i Join Date: Jul 2006 Location: UK iTrader: (0)	I've searched and found this thread, which tends to suggest that this may not be a massive issue: http://www.e90post.com/forums/showth...ons+light+335i Anyone ever heard of the emissions light being on, with no fault code? Sounds really odd to me.
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03-12-2010, 04:09 PM	#6
zltm089 Banned 243 Rep 7,690 Posts Drives: 335i SE Coupe Space Grey Join Date: Nov 2008 Location: LONDON iTrader: (0) Garage List 2006 BMW 335i [10.00]	I'm no expert....but I believe, the mechanic did mention about "lean mixture/ or fuel mixture" something when I was having problems with my one....its was just a big lump of everything....software update, solenoid valve, fuel mixture, injectors, carbon, cylinder heads....all these "technical" words were mentioned to me.....I just didn't have a clue!... I can look for email communications between me and the Workshop Manager if thats gona help? In my experience, engine warning lights or emission lights are not a good sign on a 335i.... fingers crossed in ur case ...its not major...
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03-13-2010, 07:58 AM	#7
NFS Major General 275 Rep 9,218 Posts Drives: M340i Join Date: Jul 2006 Location: UK iTrader: (0)	Light was off this morning and stayed off during a 20 mile drive. Car was parked for about 2 hours. Then the light came on as I set off for home, within about 5 minutes of starting the car. Stayed on all the way back. Engine is running fine, with no loss of power Am at a loss as to what to do next. I suppose I will ask the dealer to check for error codes on Monday and try to get them to explain everything they have checked so far. Essentially after having the car for 36 hours, they have found nothing wrong with it, other than the warning light coming on. So frustrating. I need it all of next week and am not in the mood to hand it over to them again if they have no clue what is wrong.
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03-13-2010, 08:16 AM	#8
dxb335d The Tarmac Terrorist 948 Rep 29,345 Posts Drives: 997.2 GT3 Join Date: Mar 2007 Location: ''Fandango Towers'' iTrader: (3) Garage List 2010 Porsche 997.2 GT3 [9.50] 2003 BMW E46 M3 [6.00] 2007 BMW E92 335D [5.50]	Simon, how old is your car?! __________________ 997.2 GT3
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03-13-2010, 08:47 AM	#10
dxb335d The Tarmac Terrorist 948 Rep 29,345 Posts Drives: 997.2 GT3 Join Date: Mar 2007 Location: ''Fandango Towers'' iTrader: (3) Garage List 2010 Porsche 997.2 GT3 [9.50] 2003 BMW E46 M3 [6.00] 2007 BMW E92 335D [5.50]	Registered Jan/feb? Hope it gets sorted soon mate! __________________ 997.2 GT3
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03-15-2010, 07:18 PM	#12
Serjames Colonel 128 Rep 2,426 Posts Drives: E93 335i M-sport Join Date: May 2007 Location: Surrey - UK iTrader: (0) Garage List 2007 E93 335i M Spo ... [0.00] 2003 Nissan Primera S [0.00]	I would bet a dollar to a dime this is a fault with the Lambda probes. I have a spare set you can borrow if you wish to test them.. ? The code will appear if it doesn't read a "catalysed" exhaust mixture, i.e. decatted down pipes without "mod" etc. Might be worth doing a Manual Labda probe test and getting the ACTUAL versus the displayed results. Tony's Bavarian kit could do this, or so could Birds I would imagine. It could be a damaged Catalyser - not cleaning the exhaust up enough, or perhaps a short leading to a miss-reading on the probe. You really need to get a proper independent Lambda reading from an MOT / Dyno place I think to eliminate an ACTUAL Air fuel issue. let me know about the Lambda cables, (cost me £125 and they're sitting in a box !) SJ __________________
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