i do have a soft spot for the 125 aswell! it's a very user friendly vehicle! but the 135 is more of a animal unloaded, in the wet in the form of a pannal van! be very afraid!

however, if the turbo isn't working right it's like driving into a brick wall at 3krpm, where it starts to boost then the actuater sticks and it goes into limp mode. check the wastegate actuater is moving, it should move with a little force. be carful it'll be hot so do it cold.

if your unsure best take it to ford or somewhere to be double checked.