Hello i’m new to the forum. The other day I went and got gas in the wife’s car for her. I filled it up quite a bit like I usually do I had .50 cents off so I filled it up quite a bit where you could see it in the filler neck. Drove it back home about 5 mins away and parked is for the night. Well here it is 4 days later and about 235 miles later and the gas gauge hasn’t moved any she said. But she has said the miles till empty has gone down some how much i’m not sure I have yet to get to drive it. What could it be?? There is no check engine light and car is running fine.