Due to wanting to know exactly how much fuel I'm using each time, I fill up to the top of the filler neck each time. Something happened today which I found a bit strange, and Im wondering if someone can explain.
I filled up and noticed what I presume to be some sort of breather on the left side of the filler neck right up the top.
I hang up the nozzle and notice that the level has dropped out of sight by the time I turn around to screw the cap back on.
I fill up a litte more, and thinking that there may be an air blockage in there (as I filled up with around 30% less full than my economy usually dictates) and I see fuel spewing out of the breather pipe back down into the tank. I fill up again and the same thing happens. I think I managed to squeeze another litre in, but is this normal??? Is this pipe simply a breather pipe? Why then was it spewing fuel out at me when I rocked the car??? The fuel I used was BP ultimate which virtually didn't froth at all.
What would be the best way to consistently fill up to the same level to enable accurate fuel consumption?? Should I just fill up and leave it at that the first time???