Coasting in neutral, good idea or bad?

PinchyPenny

Hi all,

This is a question for the mechanics and fuel savers.

I noticed that when driving downhill, the car rev counter would stay around 2000 rpm as I went, my foot off the accelerator pedal in top gear. Going down the same hill and placing the car in neutral I can coast along, sometimes faster, and the revs go down to around 900rpm. Am I fooling myself? Is this a 50% saving on fuel? I live in an area that I can regularly coast for up to 30 seconds.

This brings up the second part of the question, does this kind of driving cause greater wear and tear on the engine. That may seem odd, but after 3 months of this practice, my cam belt went. Yes, ouch! When I bought the car I was unable to gain the fullest history (don't harp on at me for that!) So I do not know if coasting could cause damage if it is traveling unconventionally.

I also appreciate that every driver needs to be in full ability to control their vehicle and not travel in a way that puts them self or others at risk. I do coast on roads where it is safe to do so, I can see long distances ahead of me and I live where there are low traffic volumes.

So, good idea or not?

Thanks

PP

tomstickland

An idling engine uses fuel. One that's being driven by the car rolling down a hill uses no fuel at all. However, this slows the car down more quickly.

Fuel consumption isn't directly proportional to engine rpm.

jonathon

this is illigal as you are not in full control

goldspanners

the sudden load going back on to the engine when you put it back into gear may have contributed to the timing belt snapping. and will also use up all the fuel you have just saved by coasting. its a waste of time i think.

anewman

Bad idea...

Inactive

jonathon wrote: »

this is illigal as you are not in full control

Not " illegal " as such, bad plain bad driving.

banger9365

mite be bad plain driving put a lot of the lorrys i drive that are autos will take them selfs out of gear and sit the engine at idle until you touch the acelerator or brake/ exhaust brake,when moving put we put them in to manuel when this happens to save fuel and when going down hills ect we drop it two gears(they have got 12 gears)
and boy we cant half get the mpg up on them by doing this (10mpg+)
it a shame i am not very good with my car

PinchyPenny

Hi, and thanks. I will take it then that generally it is not worth it. Like many things in life, it seemed like a good idea at the time!

sturll

PinchyPenny wrote: »

Hi, and thanks. I will take it then that generally it is not worth it. Like many things in life, it seemed like a good idea at the time!

Like getting Married

pault123

banger9365 wrote: »

mite be bad plain driving put a lot of the lorrys i drive that are autos will take them selfs out of gear and sit the engine at idle until you touch the acelerator or brake/ exhaust brake,when moving put we put them in to manuel when this happens to save fuel and when going down hills ect we drop it two gears(they have got 12 gears)
and boy we cant half get the mpg up on them by doing this (10mpg+)
it a shame i am not very good with my car

12 gears :eek: didn't realise they had so many! the mpg of lorries always makes me :rotfl:

lauren_1

What about coasting in gear?