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Old 04-10-2020, 12:36 PM   #8 (permalink)
Ecky
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Quote:
Originally Posted by aerohead View Post
Automakers discourage owners from 'topping off' modern cars due to potential harm to emission control hardware,and without topping off it's impossible to know if the tank is 'full.' Any difference is ambient 'soak' temperature only complicates the issue,on account of the 'expansion bubble' over the fuel,designed into the tank.
Short of having a removable racing fuel cell,which you could weigh,and go by fuel mass,we're all kinda SOL as far as accuracy goes now.It's very frustrating.
For a single tank, sure. We don't know when exactly it "clicks". But over a few tanks it doesn't really matter. If the tank fills a little short, it'll fill it a bit more the next time and average out the same.

Of course this is only as good as the pump's meter. There are regulations on the accuracy and testing of that.
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