I have a 2011 a4. when I first bought it, the gas reading would go all the way to 420 when filled up the car. Now it only goes to 365 on a fill gas tanK? is this a computer issue?

 

Never heard of this. There are two things that come to mind quick. One it may be calculating for summer or winter gas. The fuel companies use different mixtures in summer and winter and this greatly effects your millage (or so I have heard I dont keep close enough tabs) two it may be a hot or cold thing. When it is hot you will get more fuel in a hot tank. When the tank gets cold it contracts. Not sure if what I have said is true. LOL just things I have heard.

 

Perhaps the computer has "learned" your driving style, and knows you only get 365 miles on a tank? Those EPA estimates are based on perfect driving conditions.

I have heard that summer/ winter gas theory too.

 

My miles-to-empty-estimate-after-fillup is different every time. It's based on the miles per gallon calculation on the trip computer. I've seen anywhere from 400 to 520 on that display after filling the tank.

 

I've been reading over post and some say it has to do with driving style and also perhaps air in the tank. I tend to think it has to do with miles per gallon? I've had the car for a year 1/2 and the number is slowly declining, starting at 420 (it's never been past that) now at it's lowest at 365. I going to let it drop to 0 to see what happens. It's been unusually hot here so I don't think it's the tank expanding or contracting. doesn't get that cold in california...thanks all I welcome any other comments....