Poor MPG
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Joined: May 2009
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From: Hundred Acre Wood
My Ride: BMW 530d M Sport (58) LCI
Originally Posted by pigapumbu' post='882965' date='May 19 2009, 07:47 AM
Welcome to the truth. Anyone here who thinks they are buying a diesel and will get huge savings, please think again. Do your calculations first and ask people for real world figures.
I have a 535d which is used on a daily commute of roughly 15miles per day. I hardly ever get on the motorway for long distance trips. As I see it, the diesel doesn't have much advantage over the petrol engine car. maybe a few mph here and there but thats about it. I see 24mpg driving like a lunatic (heavy foot and making sure both turbos are used). And if I drive real slow and light footed, nothing more than 27mpg. BMW service garage tells me I am getting far better than I should hence they won't even look into it.
One needs to factor in the price difference between petrol and diesel and then make sure the diesle car returns in excess of that difference. Otherwise its a total waste of time. I haven't even got to the part of calculating the initial price to buy a diesel which tends to be higher.
As for me when I change car next, it will be a big cc engine (V8 hopefully) and use the money saved from buying a diesel car towards LPG conversion. At roughly 0.55p per litre, I will be pretty happy with that set up for a long time. Great savings, great engine sound, and great driving satisfaction when running in petrol mode with foot to the metal. Never be in a diesel again.
cheers
I have a 535d which is used on a daily commute of roughly 15miles per day. I hardly ever get on the motorway for long distance trips. As I see it, the diesel doesn't have much advantage over the petrol engine car. maybe a few mph here and there but thats about it. I see 24mpg driving like a lunatic (heavy foot and making sure both turbos are used). And if I drive real slow and light footed, nothing more than 27mpg. BMW service garage tells me I am getting far better than I should hence they won't even look into it.
One needs to factor in the price difference between petrol and diesel and then make sure the diesle car returns in excess of that difference. Otherwise its a total waste of time. I haven't even got to the part of calculating the initial price to buy a diesel which tends to be higher.
As for me when I change car next, it will be a big cc engine (V8 hopefully) and use the money saved from buying a diesel car towards LPG conversion. At roughly 0.55p per litre, I will be pretty happy with that set up for a long time. Great savings, great engine sound, and great driving satisfaction when running in petrol mode with foot to the metal. Never be in a diesel again.
cheers
I'm with you on buying a bigger engine next time, think i'll go for the m3 or m5, but maybe not convert that to lpg 
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Joined: May 2009
Posts: 43
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From: Hundred Acre Wood
My Ride: BMW 530d M Sport (58) LCI
Just got back from the dealers and the service guy i spoke to told me to do a manual calculation as sub 20 MPG isn't right. As mentioned before by someone he mentioned if anything was wrong with the car it would tell you. So he told me to calculate over three fuel fill-ups and do manual calculation of the mpg.
I asked him how low would he consider it to be before i brought it in for them to look at, he said you should be seeing (town only short drives around 1 mile) in the 30s low to mid.
He also got into how most people do calculations, as the obc isn't always correct, there are lots of factors, such as filters, brakes, start/stop etc etc etc But he said he's confident i should see 30+ but not sub 20 which i'm getting. If he's wrong i'm getting there mechanics to have a look at it!
I asked him how low would he consider it to be before i brought it in for them to look at, he said you should be seeing (town only short drives around 1 mile) in the 30s low to mid.
He also got into how most people do calculations, as the obc isn't always correct, there are lots of factors, such as filters, brakes, start/stop etc etc etc But he said he's confident i should see 30+ but not sub 20 which i'm getting. If he's wrong i'm getting there mechanics to have a look at it!
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Joined: Nov 2008
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From: Sleaford, Lincs, UK
My Ride: E60 530d M-Sport
Low 30's to mid 30's in the conditions you posted is unrealistic I think.......mid to high 20's would be a more sensible bet at best IMHO.
Im getting mid 20's around town at worst, Mid to low 30's on short trips on local A roads, and 40/43mpg on a long run @ a steady 80mph, from what I have seen elsewhere most 525d's seem to reach similar MPG to the 530d.....or slightly better on a run at best.
Im getting mid 20's around town at worst, Mid to low 30's on short trips on local A roads, and 40/43mpg on a long run @ a steady 80mph, from what I have seen elsewhere most 525d's seem to reach similar MPG to the 530d.....or slightly better on a run at best.
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Joined: May 2009
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From: Hundred Acre Wood
My Ride: BMW 530d M Sport (58) LCI
Originally Posted by Phantom Mark' post='883004' date='May 19 2009, 09:37 AM
Low 30's to mid 30's in the conditions you posted is unrealistic I think.......mid to high 20's would be a more sensible bet at best IMHO.
Im getting mid 20's around town at worst, Mid to low 30's on short trips on local A roads, and 40/43mpg on a long run @ a steady 80mph, from what I have seen elsewhere most 525d's seem to reach similar MPG to the 530d.....or slightly better on a run at best.
Im getting mid 20's around town at worst, Mid to low 30's on short trips on local A roads, and 40/43mpg on a long run @ a steady 80mph, from what I have seen elsewhere most 525d's seem to reach similar MPG to the 530d.....or slightly better on a run at best.
In any case i don't think they are going to admit that there is a problem with the mpg i'm getting ;/
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From: Scotland
Originally Posted by phileas' post='883071' date='May 19 2009, 12:12 PM
In any case i don't think they are going to admit that there is a problem with the mpg i'm getting ;/
I apologise if this has already been mentioned earlier.
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Joined: Jun 2007
Posts: 336
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From: Milton Keynes, United Kingdom
Originally Posted by pigapumbu' post='882965' date='May 19 2009, 01:47 PM
Welcome to the truth. Anyone here who thinks they are buying a diesel and will get huge savings, please think again. Do your calculations first and ask people for real world figures.
I have a 535d which is used on a daily commute of roughly 15miles per day. I hardly ever get on the motorway for long distance trips. As I see it, the diesel doesn't have much advantage over the petrol engine car. maybe a few mph here and there but thats about it. I see 24mpg driving like a lunatic (heavy foot and making sure both turbos are used). And if I drive real slow and light footed, nothing more than 27mpg. BMW service garage tells me I am getting far better than I should hence they won't even look into it.
One needs to factor in the price difference between petrol and diesel and then make sure the diesle car returns in excess of that difference. Otherwise its a total waste of time. I haven't even got to the part of calculating the initial price to buy a diesel which tends to be higher.
As for me when I change car next, it will be a big cc engine (V8 hopefully) and use the money saved from buying a diesel car towards LPG conversion. At roughly 0.55p per litre, I will be pretty happy with that set up for a long time. Great savings, great engine sound, and great driving satisfaction when running in petrol mode with foot to the metal. Never be in a diesel again.
cheers
I have a 535d which is used on a daily commute of roughly 15miles per day. I hardly ever get on the motorway for long distance trips. As I see it, the diesel doesn't have much advantage over the petrol engine car. maybe a few mph here and there but thats about it. I see 24mpg driving like a lunatic (heavy foot and making sure both turbos are used). And if I drive real slow and light footed, nothing more than 27mpg. BMW service garage tells me I am getting far better than I should hence they won't even look into it.
One needs to factor in the price difference between petrol and diesel and then make sure the diesle car returns in excess of that difference. Otherwise its a total waste of time. I haven't even got to the part of calculating the initial price to buy a diesel which tends to be higher.
As for me when I change car next, it will be a big cc engine (V8 hopefully) and use the money saved from buying a diesel car towards LPG conversion. At roughly 0.55p per litre, I will be pretty happy with that set up for a long time. Great savings, great engine sound, and great driving satisfaction when running in petrol mode with foot to the metal. Never be in a diesel again.
cheers
The reason why LPG is so cheap is 1. the government has guaranteed low tax for a specific period of time (possibly 2012, not sure). 2. there is not much demand for LPG. If government do not extend the low tax period for LPG then you could see a massive hike in running cost for LPG and may not re-coop your initial LPG conversion cost.
I think performance with LPG and fuel economy take a slight hit compared to petrol (I've ready between 5 to 10% hit on both), though cost per mile is a lot cheaper due to cost of LPG. The other thing to consider is that an after market LPG conversion is not generally liked by insurance companies and will almost certainly make it harder to sell (reducing your target market sector).
Anyway, I'm not trying to put you off, just letting you know of a few things that you may not have considered (which I found out when I was looking into doing an LPG conversion on a car I used to own).
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From: The Netherlands
Please check out my thread on replacing the EGR thermostat. My 525D 177BHP also had poor MPG 30 MPG UK or 25.5 MPG (US) (not as poor as your btw).
Dealer said it was ok but I refused to accept this answer. It turned out that the car was operating at sub normal operating temps.
The operating temp should be 90C (+/- 1C). It took a change of main thermostat and EGR thermostat (this last one is a big unknown to many dealers). to get the operating temps right.
After this my car now does between 42 and 37 MPG UK.
My advice; check the temps using the hidden OBD menu (use search function to find out how). The temps should be 90C. Also make sure you arn't mixing up UK and US MPG.
Last but not least; The big diesels MPG goed up significantly when doing urban driving. I wouldn't be surprised to get 30 UK MPG during urban driving only.
Dealer said it was ok but I refused to accept this answer. It turned out that the car was operating at sub normal operating temps.
The operating temp should be 90C (+/- 1C). It took a change of main thermostat and EGR thermostat (this last one is a big unknown to many dealers). to get the operating temps right.
After this my car now does between 42 and 37 MPG UK.
My advice; check the temps using the hidden OBD menu (use search function to find out how). The temps should be 90C. Also make sure you arn't mixing up UK and US MPG.
Last but not least; The big diesels MPG goed up significantly when doing urban driving. I wouldn't be surprised to get 30 UK MPG during urban driving only.
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Joined: May 2009
Posts: 43
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From: Hundred Acre Wood
My Ride: BMW 530d M Sport (58) LCI
Originally Posted by mini_me' post='883233' date='May 19 2009, 01:39 PM
Please check out my thread on replacing the EGR thermostat. My 525D 177BHP also had poor MPG 30 MPG UK or 25.5 MPG (US) (not as poor as your btw).
Dealer said it was ok but I refused to accept this answer. It turned out that the car was operating at sub normal operating temps.
The operating temp should be 90C (+/- 1C). It took a change of main thermostat and EGR thermostat (this last one is a big unknown to many dealers). to get the operating temps right.
After this my car now does between 42 and 37 MPG UK.
My advice; check the temps using the hidden OBD menu (use search function to find out how). The temps should be 90C. Also make sure you arn't mixing up UK and US MPG.
Last but not least; The big diesels MPG goed up significantly when doing urban driving. I wouldn't be surprised to get 30 UK MPG during urban driving only.
Dealer said it was ok but I refused to accept this answer. It turned out that the car was operating at sub normal operating temps.
The operating temp should be 90C (+/- 1C). It took a change of main thermostat and EGR thermostat (this last one is a big unknown to many dealers). to get the operating temps right.
After this my car now does between 42 and 37 MPG UK.
My advice; check the temps using the hidden OBD menu (use search function to find out how). The temps should be 90C. Also make sure you arn't mixing up UK and US MPG.
Last but not least; The big diesels MPG goed up significantly when doing urban driving. I wouldn't be surprised to get 30 UK MPG during urban driving only.
I'll check out the operating temperature. Wrt the urban drive I do get 30+ mpg, so that's not bad. It's more the town drive that shocked me.
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Joined: May 2009
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From: Hundred Acre Wood
My Ride: BMW 530d M Sport (58) LCI
Originally Posted by Bob525D' post='883172' date='May 19 2009, 12:42 PM
Can i ask an obvious question? Have you checked your cars running temperature through the hidden menu, though i would expect such a new car to have both thermostats in good working order. i have 2004 525D which gave me 22MPG, however, i changed both thermostats and i now get 28MPG. I only drive 6 miles to work and back in some stop and go traffic, a mix of 30's and 60's. I do try to take it on the motorway at least a couple of times a week.
I apologise if this has already been mentioned earlier.
I apologise if this has already been mentioned earlier.