Is fuel consumed when a car is in gear and going down a hill?

Question

Is much fuel burnt when you have your foot off the accelerator and in gear just coasting down a hill? I have a BMW with a MPG meter which displays 0 MPG when I am doing this even though the engine is still running?
I remember Jeremy Clarkson testing an Audi Diesel from Scotland to London to see how far it would go on a tank of diesel and he made some comment about the car not consuming fuel with your foot off the accelerator?

Answer 1

No,, all the above answers are wrong, the Jeremy Clarkson comment was accurate in the fact that the modern engine does not use any fuel at all while your foot is OFF the throttle and the vehicle is moving while in gear, it is the rotation of the road wheels going thru' the transmission which keeps the engine running and the engine management system shuts off the fuel supply in those times,
I dont rate the econometers in any vehicle as accurate so I wouldn't worry about what yours reads, unless your getting under 50 mls to 10 quid of fuel.
After seeing that show I tried his technique and it really does work, I now leave the car in top gear as I approach traffic lights etc and I save a lot on fuel.
After all, he made it from London to Scotland AND BACK on 1 tank of diesel in a car that even the manufacturer said couldn't be done, so even the manufacturers figures are only an estimate.

Ps. your econometer is vaccuum linked to the engine,there's probably a leak in one of the hoses which would cause the gauge to read zero.

Answer 2

Unless you have found the answer to all our power needs with that special non fuel burning engine, every time you turn your car on it is burning fuel. The meter reads 0 because it is a nominal amount of fuel you are burning. as soon as you hit the gas the meter will go up as you car is combusting faster hence using more fuel. Duel fuel cars do not use petrol when they are just ticking over as the engine can run on electricity from the fuel cells.

Answer 3

If idling your automobile calls for gas to demonstrate it. If on 'over-run', ie. it you carry off and the automobile calls for no gas to proceed shifting. eg, taking position hill in a larger equipment than standard, or lifting off the gas even as drawing near a junction the a cutting-part can received't inject any gas into the engine because it isn't required. This result can obviously be considered once you've a gas / vacation computer set to demonstrate instantaneous intake. On over-run, it is going to examine as 999mpg instead of a classic volume. So for the individuals that say you want gas to keep an engine turing - how incorrect you're...

Answer 4

As long as the engine is running you are consuming fuel -- albeit at a minimal rate...figure that a car in idle could run for days.

Answer 5

Fuel is being consumed anytime the motor is running, period. However the more you apply the accelerator, the more fuel is being used. It's that simple.

Answer 6

Fuel is consumed whenever the engine is running

Answer 7

even if your not moving and aer in nuetral you are consuming fuel

The amount of fuel increases the harder the strain on the moter is .

say you going up hill high consumption

down hill in gear low consumption

still neutral very low consumption

Answer 8

Fuel is always consumed as long as the engine is running,
It doe`s use less when coasting thats all.

Answered your vegatable Q also earlier with
LENTILS are good 4 you 2

meaning ...LENTILS are good for you too
I was given a violation for this answer
Why what was wrong with
MY ANSWER TO YOU

WILL I BE GIVEN ANOTHER VIOLATION FOR SAYING
LENTILS ARE GOOD FOR YOU again
I do like lentils in my vegatable soup.

Answer 9

yeah it's using fuel because it's running, but it depends on the speed and what gear your in, if in a low gear and it's slowing the car down it'll be using more.