Recently I acquired a 95 contour with a bad engine so I swapped it out for a good one. The car runs a little rough and is showing on my scanner that I have a bad O2 sensor this is not a big deal but what scares me is that when I give her some gas the tires will actually chirp between first and second gear and my overdrive does not seem to be doing anything even when I push the button on the console. The transmission fluid level is correct and the color good.The car seems to drive fine until you kick it down then it drops down into passing gear hard and when it comes out it is almost as hard. I really believe that the tranny is good but there is some sort of sensor or control problem .Does anyone know what sort of problem would cause this?.
