Lousy Gas Mileage in England

Rain doesn't help, but just as a guess, I'd suspect differences in the fuel.

Tom

 

<div class='quotetop'>QUOTE(bugssmith @ Feb 15 2007, 04:31 PM) [snapback]391137[/snapback]</div>

The commute change is rather dramatic. The first 5 minutes the car is warming up, so if you're spending a larger proportion of your time in the first five minutes, your gas mileage will suffer. On the positive side, you're using considerably less gasoline overall (per month).

 

<div class='quotetop'>QUOTE(nerfer @ Feb 15 2007, 05:41 PM) [snapback]391142[/snapback]</div>

Ditto what Nerver said! 10 miles doesn't seem much until you consider what happens that first 5 minutes.

 

Hi Bugs,

There are two issues with rain. First, your tires are pumping the water on the road out from under the contact patch. That is like running four several gallon per minute pumps off your Prius motor. Second, the top radiator opening is right where the air bends upward to go over the hood. Water cannot change direction as fast, and so, the water goes right into the opening, and impinges on the top of the radiator. As the top of the radiator is the hottest part, there is a maximum of conductive cooling that is, tranfer of heat to the water. Block off the top radiator opening, and you might see as much as a 5 mpg improvement.

With your short commute, the blocked off top radiator opening will get the car warming up faster, too. And since your not going to be driving slow up a desert mountain with the car (design worse case enviorment for the heater) , your not going to need to worry about running anything too hot either. Especially, not in 10 miles.

 

<div class='quotetop'>QUOTE(bugssmith @ Feb 15 2007, 05:31 PM) [snapback]391137[/snapback]</div>

Tell us more about the source of your 43. Is this an average of readings on your MFD or is it a manual calculation from tank fills? Did you have to alter the MFD to allow for the fact that the British gallon is more than the US gallon? Or are you on a US military unit which sells fuel from US pumps in US gallons?

I find mine varies a great deal because I make many journeys with a cold engine and less than 3 miles.

I keep two records: one is a note of what the MFD shows for a single journey chosen at random.
For example I drove 9 miles to a nearby town today and on the way out with a cold engine the MFD recorded 51 MPG (UK) (that's about 42 with a US gallon). On the return journey along the same route (no major hills) it was 60 MPG,UK (50 US gal). The difference is probably because the engine was cold on the outward journey. Outside temp. was about 8C. (48F)

I also keep a record of my manual calculations based on fills. The last seven fills have averaged 45.68 MPG (UK) (38 US gal) which is very low presumably because of my many short, cold, journeys in heavy traffic on town roads.

If your 43 is an average of typical MFD readings I think it's not bad for your short 10 mile trips.
I doubt whether the climate, weather or quality of fuel has very much to do with it. Maybe it's connected with traffic density? Is your present commute in dense traffic or on fast rural roads?

 

<div class='quotetop'>QUOTE(Oxo @ Feb 16 2007, 03:31 PM) [snapback]391683[/snapback]</div>

Wow with no major hills I would have expected your mileage to be much better than mine, our temperatures are about the same, we haven't broken 50 F for quite some time. But then again 4 mpg better is still better!