Okay, there is an easy way to get the correct fuel reading. I have this same problem with my car. I found this out just by chance. This is for anyone getting slow fuel readings after fill up when you know you have a full tank or have just added more gas but it doesn't show it at first and then shows it slowly rise up after driving it for a while. The easiest way to get a correct reading is to turn your ignition key to the on position, all the way to the right,
but without starting the vehicle up. Leave it in this position and then begin filling your gas tank up. While it is filling you can even sit in the drivers seat and watch the fuel needle go up along with the digital reading. Works every time and you will never have to guess if your car has a full tank of gas or not. After you start your car the levels WILL stay at the last reading. This works on partial fill ups as well. It's not a perm. fix, but it sure saves you money instead of having the fuel sensor/sendor unit replaced which is the main cause of this problem. Or paying the dealership to have it re-calibrated, which also seems to fix the problem. I would rather just sit and wait instead of spending a small fortune to get a correct gas reading.
