Hello, I have a 1997 Ford Thunderbird 4.6L V8 with the standard 4-speed 4R70W automatic transmission. I just bought the car and it has a total of 51,800 miles on it. The day after I bought it I had the ATF filter and fluid changed. Big O Tires used Valvoline Maxlife ATF. My previous car was also a '97 TBird; they used the same ATF and it worked out fine. The ATF fluid has the correct level, color, and smell. On a level surface when I am on the road and I release the accelerator, the car slows by a bit too much, almost as though the brakes are slightly being applied. When I am coasting or at a full stop and I press the accelerator, there is a slight, split second pause, then the car accelerates. When I am stopped and in Drive, the engine runs slightly rough and the transmission makes a slight turning noise. In Park, the engine runs smoothly. My previous '97 TBird did not do this. Can someone tell me what the problem is? Is it a solenoid or a vacuum sensor?