I have a 2000 Cougar, 100131 miles, V6, I travel thirty miles to Denver every weekend, on the way home when I hit 70-75 the engine starts surging until I shut the overdrive off. Any idea what could be causing this?
I've got the exact same problem with my 2000 cougar v6 with about 90k miles. While driving, the RPM's bounce around, the throttle pushes down, and the car 'surges' forward. I was told this was an O2 sensor/Cat converter problem, so I removed the cat and straight piped it, it didn't fix the problem. Anyone have any ideas?