i have a 98 expedition with a 5.4 that i just bought for my wife i have been having some problems with getting it running right. i pulled the codes it has a p1130 lack of h02s11 switch fuel trim at limit and a p0174 system too leanbank 2. i have searched for vacuum leaks cleaned the maf and fixed an exhaust leak at the manifold. i have also replaced the egr tube which was also leaking. dont have the money to throw parts at it blindly. any body help me?