thanks TKJinCNY, i'll definitely have to look into getting a set of those coils. and for the price, why the hell not, right?

 

I had significant gas mileage problems (11.x MPG city OR highway) with a 2002 F150 XLT 4.6 and the problem was a faulty coil on one of the cylinders. I bought 8 coils on ebay from Global Automotive or whatever it's called (check forums) for about ninety bucks delivered and my mileage is now about 14MPG with heavy city driving, quick acceleration, etc. I made about 18MPG highway a month ago, though.

 

Ok, so i finally calculated an accurate milage and it was pretty close to what i had guessed before, 11.6mpg is what I am getting. 2002 super crew 2wd with the 5.4L with a K&N CAI and dual exhaust. I am still wanting to replace the COP's but i figured if any of them were faulty the truck would run noticably worse and I cant tell that there is anything wrong.

 

I have seen with my 06 5.4 screw that it will get 16.5 - 17 going 75 or 13 going 85. But if you are able to go slower like 65-55 will get 20. I am running synthetic oil and at 30000 miles. It gets pretty bad if you are in the city like 13. I think most people think they can get good milage while speeding after seening the diference going slower is worth it to me.

 

Tune it. Factory tunes are made primarily to appease emmisions rules. You can lean out the air/fuel mixture a little quite safely. while not a major gain, you might get 1-2 out of it. Also keep in mind more weight = less mpg. Carrying stuff round in the back adds up.