Okay.
My swift has a massive fuel gauge. It's basically bigger than Corollas fuel gauge.
First 10% of the fuel gauge is 10 litres. The rest 90% is 42 litres.
Now, after I come close to 17 litres left in the tank, every line = '_' equals 2 litres.
I can Estimate, I repeat, Estimate how much fuel I have left, Estimate meaning not 100% sure, just close to.
The correct and easiest way is to get a full tank on auto refill on medium speed, drive till it becomes low again, go to same pump and repeat the procedure.
Enjoy tank to tank fuel measurements
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