I seem to remember somewhere that the GT has a Ford Focus steering column. This is a common problem with the Ford Focus. Maybe a look into their forums would help
Try opening and closing the hood, making sure it's closed. I don't think this is your problem but it wouldn't hurt to try. An open hood could effect wiper operation.
On the front of engine, passenger side, on the intake manifold just behind the fuel rail and radiator hose is a vacuum nipple. I used this and it worked out very well.
The cooling effect of water injection fools the engine into thinking it has higher octane, that was the original idea. It allowed higher compression in airplane engines.