I too have ab13 with ab14 engine. Had a similar problem recently, bought a new throttle body and problem was solved.
When I say new, I mean second hand.
Btw, there's a b13 and a b14 club on Facebook where there's a lot is support.
Search for ClubB13TT and Club b14 tt
TurboSingh12 wrote:Service the iacv or throttle body