so was losing gas mileage from 31 to 24 in matter of 4 months had is checked out the brake booster has a bolt going thru it and i believe it did somethin to on of my vaccum sucking in air. my trusted mechanic says it looks like it was installed there from the factory, my question is its an 05 would it take this long for the problem to start? is there anything i could do i guess legally?

 

I think if your brake booster were responsible, you would ALSO have problems with your brakes. Are they operating normally?