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Hi all, I'm after a bit of advice...
On the last tank of fuel, I noticed quite a drop in MPG, down from 31 average to 26 average. I've never been that impressed with the 31 to be honest, but 26 is pretty poor for a diesel isn't it?
I'm wondering if something is wrong and perhaps the ECU is reading a cold temp and over-fueling? Could the cold temps of late back this theory up?
Anything worth checking out?
Cheers
On the last tank of fuel, I noticed quite a drop in MPG, down from 31 average to 26 average. I've never been that impressed with the 31 to be honest, but 26 is pretty poor for a diesel isn't it?
I'm wondering if something is wrong and perhaps the ECU is reading a cold temp and over-fueling? Could the cold temps of late back this theory up?
Anything worth checking out?
Cheers
I did 25k miles in 11 months in my 535d and that averaged 25.9mpg.
Even when not hacking it the best was 32mpg.
Went up a little in the summer, but overall it was 26mpg.
Had a 335i and that was also 26mpg.
Had a 530i and that was also 26mpg.
Had a 330d auto touring and that was 30mpg.
Now stopped buying diesels unless they are small cars and smaller engines.
Even when not hacking it the best was 32mpg.
Went up a little in the summer, but overall it was 26mpg.
Had a 335i and that was also 26mpg.
Had a 530i and that was also 26mpg.
Had a 330d auto touring and that was 30mpg.
Now stopped buying diesels unless they are small cars and smaller engines.
Thanks all.
Something deffo wrong with mine. Average is down to 25ish now and I drove steady all the way to and from work (60mph ish).
I don't think it's warming up properly - the rev limiter never got above about 4.5k in the twenty minute journey.
Thermostat sticking open? I'm assuming diesels work the same as petrol - i.e. over fuel when cold?
Something deffo wrong with mine. Average is down to 25ish now and I drove steady all the way to and from work (60mph ish).
I don't think it's warming up properly - the rev limiter never got above about 4.5k in the twenty minute journey.
Thermostat sticking open? I'm assuming diesels work the same as petrol - i.e. over fuel when cold?
boony said:
Thanks all.
Something deffo wrong with mine. Average is down to 25ish now and I drove steady all the way to and from work (60mph ish).
I don't think it's warming up properly - the rev limiter never got above about 4.5k in the twenty minute journey.
Thermostat sticking open? I'm assuming diesels work the same as petrol - i.e. over fuel when cold?
How far is work??Something deffo wrong with mine. Average is down to 25ish now and I drove steady all the way to and from work (60mph ish).
I don't think it's warming up properly - the rev limiter never got above about 4.5k in the twenty minute journey.
Thermostat sticking open? I'm assuming diesels work the same as petrol - i.e. over fuel when cold?
The big diesel takes around 12 miles or 20 minutes to get to temperature when it is around 3°c outside, up until this point it is gobbling fuel.
My 3.2 petrol A6 is more economical than my 535d touring was for getting into the city and back, which is 9 miles each way. It is on long runs where the diesel starts to show its benefits.
It's a rev limiter from memory, keeps the revs down till the temp is high enough, I don't think they all disappear, two or so remain from memory.
15 miles, cold temperatures, sounds about right.
Drive your car for 30 minutes, this will get it to full temperature, or as near as damn it, and then get onto the motorway, stick it on cruise at 70mph and see what you get when you reset the OBC, should be around 36-38mpg over 5 miles or so if there is no heavy traffic and no braking etc.
Try and do it without heated seats on, no lights, and at midday so the heaters aren't working overtime, or turn the heating off for the test.
If you are still getting 25mpg then you have a problem, if you do get 36ish then you know it is alright and just down to temperature.
I know somone who did 220k miles over 3 years in his 530d auto SE and he averaged 31mpg, that was a proper mpg, not resetting it everytime it dipped low to massage the figures again, that was reset on services only and it always sat at 30.6mpg he said, sometime took a week to get there and sometimes a month, but it always ended up back at 30.6 for him in the end.
15 miles, cold temperatures, sounds about right.
Drive your car for 30 minutes, this will get it to full temperature, or as near as damn it, and then get onto the motorway, stick it on cruise at 70mph and see what you get when you reset the OBC, should be around 36-38mpg over 5 miles or so if there is no heavy traffic and no braking etc.
Try and do it without heated seats on, no lights, and at midday so the heaters aren't working overtime, or turn the heating off for the test.
If you are still getting 25mpg then you have a problem, if you do get 36ish then you know it is alright and just down to temperature.
I know somone who did 220k miles over 3 years in his 530d auto SE and he averaged 31mpg, that was a proper mpg, not resetting it everytime it dipped low to massage the figures again, that was reset on services only and it always sat at 30.6mpg he said, sometime took a week to get there and sometimes a month, but it always ended up back at 30.6 for him in the end.
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