Anyone else have a drop in MPG?

madman · 01-05-2009, 07:59 AM

My car had a 25% reduction in MPG and also a strange petrol smell every so often when I put it in the garage.

While I was in the dealers getting it looked at, the woman in front of me had the exact same issue.

They told me it was a build up of sulfur in the Cat Converter. They put it on a 'clean mode' then told me to drive it down the motorway for 30 miles.

Well, it certainly did the trick, my MPG went back up over 40mpg and even after taking it for a burn it never went below 40mpg!

If anyone else is having a drop in MPG get it checked....it might not be your driving!!

PhilR · 01-05-2009, 08:08 AM

I posted a thread about my deminishing MPG some weeks ago. Incidentally I have a D but the economy has dropped at least 3 MPG.

I thought modern engines (particularly diesels) burnt off soot particles when the cars particulate sensor is triggered - hence the "eggy smell" you get now and again?

I am due for a service in 1,100 so hoping this will help the car return to 37mpg (currently 33/34)

madman · 01-05-2009, 08:16 AM

might be worth getting it checked. although your drop in mpg is relatively low compared to what i was getting.

I normally get around 41mpg, recently that dropped down to 32mpg and no matter how i drove it it wouldnt go higher than 34. Its not back to normal though.

PhilR · 01-05-2009, 08:20 AM

Madman - Is yours a diesel or petrol?
I am guessing a D from the 41mpg you quote

madman · 01-05-2009, 09:33 AM

Petrol. its only the 320i though which has similar MPG to your 330d

I was quite surprised with the mpg though, impressive for this car.

biscuits · 01-05-2009, 10:02 AM

You sure it's not due to the cold weather starts. Mine is taking longer to warm up in the morning at the moment and drinking more that normal.

beemerbird · 01-05-2009, 10:08 AM

Quote:

Originally Posted by biscuits

You sure it's not due to the cold weather starts. Mine is taking longer to warm up in the morning at the moment and drinking more that normal.

+1 Mine has dropped since it's been cold. Don't know how accurate this article is :

http://www.timesonline.co.uk/tol/new...cle5360935.ece

madman · 01-05-2009, 10:24 AM

Mine definitely had a fault which got fixed today. I think PhilR with a 3mpg drop might be due to cold weather. I had a drop of 10mpg which is pretty significant. All fixed now though. I'm thinking of leasing a room at the dealership with the amount of time I spend in there.

madman · 01-05-2009, 10:26 AM

Quote:

Originally Posted by beemerbird

+1 Mine has dropped since it's been cold. Don't know how accurate this article is :

http://www.timesonline.co.uk/tol/new...cle5360935.ece

WOW....50%....yikes.

Mine actually seems more fuel efficient since i got it back though. Will be interesting to compare the results of a full tanks worth.

beemerbird · 01-05-2009, 11:29 AM

Quote:

Originally Posted by madman

WOW....50%....yikes.

Mine actually seems more fuel efficient since i got it back though. Will be interesting to compare the results of a full tanks worth.

My E90 330i used to get the sulphur smell but not with any noticeable drop in mpg. I didn't realise this 'clean mode' could be done on the petrols though.... like on the diesels.

Sure the 30 miles 'blast' was a chore though eh.

madman · 01-05-2009, 11:33 AM

Haha.. If i was alone it would have been a blast, but i was with he wife who is still recovering from a car accident we had last year. DOH.

beemerbird · 01-05-2009, 11:58 AM

Quote:

Originally Posted by madman

Haha.. If i was alone it would have been a blast, but i was with he wife who is still recovering from a car accident we had last year. DOH.

Oh yes I remember ............hope she's going on ok and still receiving physio to help her?

madman · 01-05-2009, 12:36 PM

she's recovering slowly....very slowly. Thanks for asking. (me) Driving freaks her out a bit and she can get very panicked so i have to keep my overtaking etc to a minimum.

She's just been prescribed some Valium though so that should chill her out a bit

01-05-2009, 07:59 AM	#1
madman Major 108 Rep 1,252 Posts Drives: The Above Join Date: Nov 2007 Location: Lincolnshire, UK iTrader: (0)	Anyone else have a drop in MPG? My car had a 25% reduction in MPG and also a strange petrol smell every so often when I put it in the garage. While I was in the dealers getting it looked at, the woman in front of me had the exact same issue. They told me it was a build up of sulfur in the Cat Converter. They put it on a 'clean mode' then told me to drive it down the motorway for 30 miles. Well, it certainly did the trick, my MPG went back up over 40mpg and even after taking it for a burn it never went below 40mpg! If anyone else is having a drop in MPG get it checked....it might not be your driving!! __________________ If you're not living on the edge, you're taking up too much space.
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01-05-2009, 08:08 AM	#2
PhilR Second Lieutenant 9 Rep 283 Posts Drives: E93 330d M Sport Auto Join Date: Mar 2008 Location: Teesside / Surrey iTrader: (0) Garage List 2002 Mercedes CLK 3 ... [0.00] 2007 Audi Q7 S Line ... [0.00] 2006 (56) 330d M Sp ... [0.00]	I posted a thread about my deminishing MPG some weeks ago. Incidentally I have a D but the economy has dropped at least 3 MPG. I thought modern engines (particularly diesels) burnt off soot particles when the cars particulate sensor is triggered - hence the "eggy smell" you get now and again? I am due for a service in 1,100 so hoping this will help the car return to 37mpg (currently 33/34)
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01-05-2009, 08:16 AM	#3
madman Major 108 Rep 1,252 Posts Drives: The Above Join Date: Nov 2007 Location: Lincolnshire, UK iTrader: (0)	might be worth getting it checked. although your drop in mpg is relatively low compared to what i was getting. I normally get around 41mpg, recently that dropped down to 32mpg and no matter how i drove it it wouldnt go higher than 34. Its not back to normal though. __________________ If you're not living on the edge, you're taking up too much space.
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01-05-2009, 08:20 AM	#4
PhilR Second Lieutenant 9 Rep 283 Posts Drives: E93 330d M Sport Auto Join Date: Mar 2008 Location: Teesside / Surrey iTrader: (0) Garage List 2002 Mercedes CLK 3 ... [0.00] 2007 Audi Q7 S Line ... [0.00] 2006 (56) 330d M Sp ... [0.00]	Madman - Is yours a diesel or petrol? I am guessing a D from the 41mpg you quote
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01-05-2009, 09:33 AM	#5
madman Major 108 Rep 1,252 Posts Drives: The Above Join Date: Nov 2007 Location: Lincolnshire, UK iTrader: (0)	Petrol. its only the 320i though which has similar MPG to your 330d I was quite surprised with the mpg though, impressive for this car. __________________ If you're not living on the edge, you're taking up too much space.
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01-05-2009, 10:02 AM	#6
biscuits Dimmer than a dim thing 80 Rep 1,291 Posts Drives: M4 GTS, EQC, X5 40d, simrig Join Date: Oct 2008 Location: UK iTrader: (0) Garage List 2016 BMW X5 (F15) 4 ... [0.00] 2016 BMW M4 GTS [10.00]	You sure it's not due to the cold weather starts. Mine is taking longer to warm up in the morning at the moment and drinking more that normal.
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01-05-2009, 10:24 AM	#8
madman Major 108 Rep 1,252 Posts Drives: The Above Join Date: Nov 2007 Location: Lincolnshire, UK iTrader: (0)	Mine definitely had a fault which got fixed today. I think PhilR with a 3mpg drop might be due to cold weather. I had a drop of 10mpg which is pretty significant. All fixed now though. I'm thinking of leasing a room at the dealership with the amount of time I spend in there. __________________ If you're not living on the edge, you're taking up too much space.
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01-05-2009, 11:33 AM	#11
madman Major 108 Rep 1,252 Posts Drives: The Above Join Date: Nov 2007 Location: Lincolnshire, UK iTrader: (0)	Haha.. If i was alone it would have been a blast, but i was with he wife who is still recovering from a car accident we had last year. DOH. __________________ If you're not living on the edge, you're taking up too much space.
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01-05-2009, 12:36 PM	#13
madman Major 108 Rep 1,252 Posts Drives: The Above Join Date: Nov 2007 Location: Lincolnshire, UK iTrader: (0)	she's recovering slowly....very slowly. Thanks for asking. (me) Driving freaks her out a bit and she can get very panicked so i have to keep my overtaking etc to a minimum. She's just been prescribed some Valium though so that should chill her out a bit __________________ If you're not living on the edge, you're taking up too much space.
	Appreciate 0 Quote