Stupid question of the day number 2

Instantaneous MPG, or average MPG on the Consumption screen?

-m.

 

How close to "the begining"? Nice warmed up car filled then driven at 35 on the flat will have better mpg than later in the tank when you have had a lot of cold starts, highway driving, etc

 

Hmmm, interesting. For us, filling with a warm tank yields good numbers at first getting worse over time. Filling with a cold tank yields poor numbers at first, getting gradually better.

However, no matter what the conditions are when filling the tank, we nearly always finish the tank at an average of 4.6 litres per 100 km. It's maddenly predictable.

 

I'm guessing it's because the car burns more gas during warm-up. You're filling after warm-up, so that first morning's drive gets better mileage. After that, it settles down to the real average.

Either that, or it's just a coincidence. Something different about that first day's driving after the fill-up is getting you better mileage, and then it settles back down to the real average.

The temperature of the tank or bladder should not matter, since the car is (so I've heard) just measuring or calculating the amount of gas injected into the engine, irrespective of how much is in the tank.

I'm at about 51 mpg, very near the beginning of a new tank, but it reached 54 during the first day's driving after filling up. Your mileage, by all accounts, will improve significantly as the car gets broken in. Oh, and I didn't run the engine before filling the tank this time.

Hey!!! I wonder if cold gas could give better mileage? Freshly pumped out of the underground storage tank it's cold. Cold gas burns better? Or ignites differently? Or more gets injected than the car thinks???