I have a 1998 Ford Windstar with the 3.8L Motor. Starting about a month ago, I noticed that at idle, in Drive, the vehicle still pushed forward. The brakes still held it, but I could feel it intermittantly pushing against them. At the same time, the rpm would drop during the push. It would be the same as someone not fully disengaging the clutch on a manual. Unfortunately, the problem has been getting worse, and what was before an occasional issue has become regular, with the surging happening whether in Park, Neutral, or Drive (but stopped). Sometimes it will even stall the engine. Fuel economy has dropped considerably also. Oddly enough, when I put it in drive, and let off the brake, it scarcely moves at idle. Any ideas as to what could be the issue would be appreciated. My suspicion is the TCC, but I'm not certain.