Not unless you were doing moronic speeds on the motorway.
What is most likely to cause high fuel consumption?
- Thread starter azmi
- Start date
Not unless you were doing moronic speeds on the motorway.
It depends on your speed, but i was trying to say that it can be fuel expensive to do stop\start driving.
No chance, I'll be lucky to get 25-30 at 30 through town. Easy get 37~ on the motorwat sitting at 70~.
the correct answer is: driving above 50 mph
my first answer is agrresive braking , but the correct answer is driving above 50mph...
i do some question papers, aggresive braking and acceleration will consume more fuel will be the asnwer, but the above question is difeerent...anybody can tell me why driving above 50 consume more fuel? ...
my first answer is agrresive braking , but the correct answer is driving above 50mph...
i do some question papers, aggresive braking and acceleration will consume more fuel will be the asnwer, but the above question is difeerent...anybody can tell me why driving above 50 consume more fuel? ...
Soldato
- Joined
- 29 Jun 2004
- Posts
- 12,957
I'm guessing it's taking the engine a lot more work to overcome wind resistance which gradually becomes more turbulant as you cut through it, which means more fuel is spent causing a net movement in the direction you want at a constant speed.
I think the test is wrong, I've done a long run with my car at 55MPH and averaged 35MPG, did another run at 78MPH and got 38MPG. Both runs were ~250 miles. I emailed the guy who runs the website asking for clarification anyway.
Soldato
[TW]Fox;14720289 said:
Poorly worded question and assumptions all round.
Braking aggressively does not increase fuel consumption at all.
Braking to a stop, aggressive or not doesn't increase consumption.
However, as you all have pointed out, braking when you don't have to, does.
However, this is all about assumptions and they probably mean still moving, not stopping.
Oohhh I hate theories, half of them need to be re-written. (at least in jersey).
Soldato
Theory test answer is C, Driving above 50mph as agressive braking, does not mean you have accelerated aggresively.
50 MPH is generally seen as the most economical "average" speed by the authorities, although like the braking it depends on the vehicle you are driving and how you are driving.
50 MPH is generally seen as the most economical "average" speed by the authorities, although like the braking it depends on the vehicle you are driving and how you are driving.
Soldato
Standing still in traffic kills my fuel economy. I get 10mpg and that's only because the guage won't display any lower than that.
Soldato
I get much better economy at 80mph than I do at 60 or 70. No idea why though. I'm driving up to York later tonight so I'll test this out again (assuming the traffic isn't too bad)
Something to do with gearing I'd imagine.
I remember when I had my space saver spare wheel on and had to get to work down the A380, so had to do 50. My fuel consumption was reading 95mpg by the end of it
- I can only think that the guage gets less accurate either side of the average norm
I remember when I had my space saver spare wheel on and had to get to work down the A380, so had to do 50. My fuel consumption was reading 95mpg by the end of it
- I can only think that the guage gets less accurate either side of the average normI totally disagree with that test.
Driving above 50mph should significantly decrease fuel consumption. Assuming it's a constant speed in a high gear.
Aggressive braking would definitely increase fuel consumotion, purely for the reason that your wasting energy that you've already used up. Scanning the road ahead and using acceleration sense to avoid braking altogether uses far less fuel.
Driving above 50mph should significantly decrease fuel consumption. Assuming it's a constant speed in a high gear.
Aggressive braking would definitely increase fuel consumotion, purely for the reason that your wasting energy that you've already used up. Scanning the road ahead and using acceleration sense to avoid braking altogether uses far less fuel.
Soldato
Soldato
My record MPG was done at 56MPH!
Caporegime
Soldato
Aggressive braking & Going above 50mph
why?
Braking is burning off energy you used (fuel) to get moving. Try and coast up to lights, never brake on motorways just look far ahead and ease off etc.
Going above 50mph, drag gets higher and higher the faster you go so car has to work harder. Gearing causes the exact figure to change, so some cars may be able to cruise at 65-70, were as my shopping trolley looses mpg at anything over 50. IE 50mph is 40mpg, 70mpg is 31mpg etc.
why?
Braking is burning off energy you used (fuel) to get moving. Try and coast up to lights, never brake on motorways just look far ahead and ease off etc.
Going above 50mph, drag gets higher and higher the faster you go so car has to work harder. Gearing causes the exact figure to change, so some cars may be able to cruise at 65-70, were as my shopping trolley looses mpg at anything over 50. IE 50mph is 40mpg, 70mpg is 31mpg etc.
Last edited:
Associate
Do NOT do this on your practical test, you will fail or get a minor at the least. The DSA Examinors will expect you to change down gear when approaching things you have to slow down and stop at (until you come to a near stop, obviously)