Bad Fuel Economy. PLEASE HELP

[Elmobile]

I have a 2008 Ford Ranger Supercab 2Dr. XLT 4x4 with the 4.0L V6. I have modified the vehicle with a cold air induction system from K&N. I have also added a Superchips upgrade and had the system reprogrammed for fuel economy optimization. I also installed a dual exhaust system. As far as maintainance goes. I change the oil religiously every 3,000 miles. I make sure the tires have the correct tire pressure. The vehicle has been aligned. I have even had the collant system and the fuel system completly flushed. I haven't had any trouble codes or check lights come on at all. I used to get 14 to 15 mpg city and 18 to 20 mpg hwy. After 46,000 miles since buying it brand new of the lot I now get 10 to 12 mpg city and 15 to 16 mpg hwy.

Those modifications were made after the fuel economy dropped. Can anyone please help me with this problem and tell me if there is something I can do to fix this?

Thanks.

 

[Elmobile]

My driving habits have not changed and I actually drive more carefully now than I did when I bought it.

 

[Gatorjoe]

My first thoughts would be to change the fuel filter and clean the mass airflow sensor. Since you said mods were post problem, that's where I'd start.

 

[CoyoteHunt]

Had the same problems as the OP mines an 09 SC Sport 4X4 4.0 changed Fuel Filter and MAF took her for a real good boot today will fill up when tank hits E but so far I am liking what the gauge is showing for the milage I am getting keep in mind mine is stock other than the K&N drop in filter.

 

[Elmobile]

I will definitely try that. Sounds simple.

*just FYI: if you do install the K&N induction system it adds about 12HP officially according to K&N but I think that figure is a little low. The system also becomes very noticable with the sound from the air being sucked in so must faster than the stock system. Bottom Line: its adds HP and bosts performance but the sound may drown out the dual exhaust system because its so loud.*

 

[kkjb4x4.0]

If you oil your filter your gonna gunk up your sensors,,start by cleaning your maff and any other sensor between your filter and intake!