kovacsr15

My 2004 GT 4.6 Auto fully stocked is only getting about 12-13 miles per gallon mostly highway miles. The car runs fine fully stocked except for flo masters, no tune (I've had enough issues with them). Things done recently with car, new air filter, clean mass air flo censor, new fuel filter, new plugs but Im not sure what type were put in, copper core etc., The only thing I noticed at wide open was that sometimes it feels like somebody is pushing me from behind, and I don't know if that was a slight miss, I don't know much about cars.
thanks, any suggestions or is this just normal?
-dave

96t-bird

Your car should be getting at least 17-20 mpg on the hwy. What gears are you running in your car? Any cel?

kovacsr15

the gears are 327 stock,any thoughts

mustangman02232

My 99 GT vert did 22-23 mpg, which was better then my v6, check tire preasure and the front end alignment to

kovacsr15

I have 327 any thoughts.

96t-bird

You stated a lot has already been done on your car. Has the check engine light came on ? possibly your transmission is slipping,other wise. you are not measuring the MPG correctly. Good luck