So i pit on an airdog2 165, last week and noticed a huge drop in milage. Like from 17 in town to around 10 and 22 hw to about 15... I have checked for leaks all over and nothing. I put in new stock air filter also. Truck has full egr delete 4" straigt. And efi by idaho rob. 1/2 cp3 inlet fitting. What could be causing this? Please help!