I have a 1999 dodge ram 1500 sport with a 318 and i put on a AEM Brute Force cold air intake on my truck 2 days ago. before i put it on i was getting 10.7 mpg now im getting 8.5 mpg with it on. its suppose to make my gas mileage better not much worse. whats going on someone help any ides or info would be nice thank u

 

It's possible you could have knocked some gunk down into the throttle body and either clogged things up or fouled the sensor when you removed the stock components. You may need to remove the CAI and give the TB & sensor a good cleaning...