I assume you mean the black and grey MTH Z-4000 transformer with two handles (and 360 watts).
I'm not sure if a 9 year old TIU was a Rev. L model or not.
Just to clarify, if you have one handle output of the transformer hooked up to TIU Fixed Input 1 and then from TIU Fixed Output 1 to the single piece of track with the PS3 engine on it, what happens ?