E280 CDI MPG computer

[mbenz1]

Hi

After resetting the MPG on the on-board computer, it shows 40MPG, how long does it take for the computer to show the real MPG vaue as I heard that it takes some time to come down to the actual MPG value. ALSO, can anyone advise on a typical lifetime of the MAF sensors in these engines?
thanks in advance.

 

[mbenz1]

Any advice would be great

 

[Deleted member 37751]

I would say that it sets itself pretty quickly, maybe a mile or so.

Why do you ask? You must be covering short journeys if you aren't confident in the readings.

 

[mbenz1]

SPX.. what happens is it actually keeps decreasing very slowly, around 0.1 mpg per 3-5 seconds and sometimes it increases suprisingly - it seems to be fluctuating up and down but mainly decreasing. So due to that, i guess it would take a few miles for it to come down to the actual value?