I've noticed I am getting pretty bad gas milage. I put 10 gallons in last night, I've driven 40 miles literally hafl freeway/half streets. When I filled the tank, the needle just barely reached the full mark. Now its a little to the left the line before the full line. Also, I dont know if I am hearing things, but I hear a whooshing/sucking sound when I press the gas pedal. Could whatever that is be a link to the bad gas milage? I know I need new plugs/wires and a fuel filter, but the milage seems to be getting worse since when I got the car