Increased use of petrol/winter fuel

OddballJamie

Kitty777 wrote: »

The cheapest one in town is only like 0.5 miles away, and on my way home from my friends (which i cannot walk too!!) and the second cheapest is where I do my 2 weekly shop

And Justin is more than welcome too, but that may be a bit impractical :P

I wouldn't recommend walking to the petrol station, you'll get it all over your shoes.

Ultrasonic

Kitty777 wrote: »

I do only short journeys, probably between 2-10miles each time and longer journeys about once a month. My predications are that I will lose about 60 miles or so this month...is this acceptable and normal?

Two thoughts:

1) It is perferctly normal for mpg to drop as the weather gets colder and wetter.
2) How have you calculated your 60 mile loss, and what exactly do you mean by this actually?

Kitty777

OddballJamie wrote: »

I wouldn't recommend walking to the petrol station, you'll get it all over your shoes.

I meant I cannot walk to my friends, incase someone said that it will be saving petrol if I did or something like that.

:rotfl: I cannot say anything right, can I? :P

Kitty777

Ultrasonic wrote: »

Two thoughts:

1) It is perferctly normal for mpg to drop as the weather gets colder and wetter.
2) How have you calculated your 60 mile loss, and what exactly do you mean by this actually?

I haven't changed my driving habits of driving style, and to be honest it is just an estimate. Usually I get 80 miles for 1/4 of a tank and now I am getting like 65miles or so.

I do just want to say (before an arguement occurs) that due to my autism I do tend to overthink things and I slightly panic when things change like this. Hence why i am so obsessed with numbers.

But if this is all 'okay' and 'acceptable' then I can relax a little.

Iceweasel

Fuel gauges are famed for being not as accurate as many people think.

The only accurate way to check mpg is to fill the tank to the brim then after say 200 miles or so, fill it to the brim again and then do the sums.

A 10% drop in mpg in the winetr is normal - especially on short journeys of the type you do.

Don't worry about it - it is normal.

You can relax.

Kitty777

Iceweasel wrote: »

Fuel gauges are famed for being not as accurate as many people think.

The only accurate way to check mpg is to fill the tank to the brim then after say 200 miles or so, fill it to the brim again and then do the sums.

A 10% drop in mpg in the winetr is normal - especially on short journeys of the type you do.

Don't worry about it - it is normal.

You can relax.

Thank you for your reply

I have noticed that it isn't accurate. I have driven a few miles or so with the 'petrol light' on and then went to fill it up and it is only like 38L (i think it is a 45L tank?) There does seem to be more petrol in the tank then the car tells me

simon06

Lambda sensor or one of the other engine management sensors going faulty?
Any smells of petrol around and under the car ?

Kitty777

simon06 wrote: »

Lambda sensor or one of the other engine management sensors going faulty?
Any smells of petrol around and under the car ?

No smell of petrol. I have had an engine management light come on a few times over the past 2 years (fuel trim?) or something...but it is very intermittent and I have had advice from a mechanic and my partner who seems to know his stuff and it isn't anything to worry about. When the light has come on, there hasn't really been anything different in the fuel usage even though the engine could be running rich/lean.

It has just happened as the weather has got darker and colder, hence why I assumed it was that. My MOT in april showed that the emissions test (which includes the lambda sensor bit? or something to do with that) was 99.999% perfect. but that was 7 months ago now.

Herzlos

JustinR1979 wrote: »

You are wrong - darkmatter is back and promised to not post nonsense


I've never heard of reducing pressures for icy roads.

I can only see it making sense if you're completely stuck in snow (not ice), and then once you're free stopping somewhere safe and re-inflating them. For normal driving it's just stupid.

Ebe_Scrooge

MPG will always drop in winter to some degree. As previous posters have said, using more electrical equipment ( lights, demisters, heated seats, fans etc ) "costs" fuel - the electricity doesn't come from nowhere.

Also the roads tend to be wet for a large proportion of the time. Any time you drive through a large puddle, you'll notice the quite dramatic amount it slows the car down. If the roads are wet, you're constantly "driving through a puddle", so to speak. Not to the same extent as a large deep puddle, but it'll slow the car down nonetheless. Or to look at it the other way, you need to burn more fuel to maintain a given speed, compared to a dry road.

And the engine takes longer to warm up to normal temperature. Whilst it's cold it's not as efficient. Anyone remember the old days when we had a choke that we pulled out when it was cold ? All that did was enrich the air / fuel mixture. These days it's controlled electronically, but the engine still needs a richer mixture when it's cold.

All these things combined will reduce the MPG.

Oh, and the idea of only filling the tank half full to reduce weight is nonsense for all practical purposes. In theory yes, any extra weight will reduce efficiency. In practice the difference between a full tank and a half tank will be so small as to be un-measurable. You'd do more good by removing the spare wheel and taking out any seats you're not using :-)