ChipF47, I picked my car up from a local import garage on Friday. It turns out that when I took my car to have Pep Boys perform the tune up they installed Platnium spark plugs. Once a new set of copper plugs were in the car, it was up and running. No more black smoke. He said that Z cars do not like Platnium plugs. The TPS is on the side of the AFM. 2 screws and a connector. Good Luck. Dale