maybe its my gas tank?

[Unit 5302]

Originally posted by Crazy Horse GT
no flames, lol j/k with ya, -- are you holding the handle wide open? we have a chevy truck , at work, if you hold the nozzle wide open, it kick's off after 3 second's, have to hold it halfway or less, it's a pita, but, am i close or not. really i'm telling the straight up on this. good luck

The Matrix uses a 13.2 gallon fuel tank in the non-AWD models. This means at empty, you probably still have more than a gallon left. So at 12 gallons for 360 miles, you're getting 30mpg. If you were to get only 300 miles, it would still be 25 miles per gallon, and at 345 you'd be sitting at nearly 29mpg.

A mix of more city driving than normal, coupled with the A/C would easily account for the drop in fuel economy. No offense, but I believe you have the 130hp version. Even with better than 250hp, and a ton of torque, my 88, 87, and 02GT's suffered 2-3mpg for running the A/C all the time. With 130hp and less torque, it's going to significantly pull on the little engine, especially at lower rpm to keep the A/C running. No joke, but the A/C can rob significant horsepower.

In regards to your gas filling problems, I've had the same problem from time to time in many of my cars. A lot of modern gas stations have powerful pumps that simply pump more fuel than what your tank's filler neck can get into the tank. This causes a backup of fuel in the filler neck, and that trips the sensor on the filler nozzle resulting in the fuel flow stopping.

As Crazy Horse GT stated, just don't hold the filler wide open, and you should have no problems.