Fuel Economy C200k

[Cheltenhamshire]

A bit of a weird question this one. My commute to my Cheltenham office is about 7 miles on an a-road and skirting around the town centre and up a hill for 2 miles.

In the morning I seem to get 23mpg average so the computer tells me. Yet when I return the same day and reverse the journey I get 32mpg.

Why is this?? Is the cold start of the morning really sucking that much extra fuel?? I am sure that going down the hill at the end of the day will give me some fuel saving but certainly not 10mpg!!

Incidentally the same thing happens on my commute to the London office, 33mpg average going to the office with 35-39mpg on the return!!

Any ideas??

 

[jberks]

probably traffic flow more than anything else. Any hold ups and you're using fuel and not moving - mpg - especially on a 7 mile journey, falls through the floor. Temp is probably irrelevant as it doesn't fully warm up on either journey.
Add in inclines and acceleration and you have your answer.

I get 42 on the way into work. I leave at 6:30 so cruise to the motorway, but then hit the motorway traffic and mostly trundle at 60-70 for the 32 miles over the pennines, followed by a slow but moving 7 mile drive into the city. The way home is similar but a little faster, and she often reads 41 as I get off the motorway.
However, I then hit rush hour town traffic and have a crawl past the city centre, followed by rat runs to bypass the major queues. If she only drops to 36 at the end of that I've done well.