ah i see how it works now. i guess i will have to change the fill up process, but the thing is when filling up a car every pump slightly differs in how fast the gas comes out and the faster it comes out the more it foams up and causes the nozzle to shut off early. so i guess i will just put it on the slowest setting til it clicks and wait a 10-15 seconds and start it again til it shuts off and call that filled up. that is what it suggested online. I dont like this because I feel the numbers are going to be inaccurate but i dont want to mess up my engine. for info on this just google evaporative emissions control system.