I really need some advice. I have a 2001 Mercury Cougar that I bought 2 years ago. It has 140k miles on it and the engine sounds strong and it idles and drives great until two weeks ago. This is the problem I am having. I was driving with the wife and kids and the was doing about 50 mph. The car loss Engine power and bucked but not electrical power and completely stalled at those speeds. I preceeded to pull off the road and try and start the car. It started and idle normal but would just shut off. I figure try it again and did the same thing. Then tried it one more time and I would not even get it to crank at all. I would turn the key and the electrical power would be on but the starter would not kick over to start the car. I figure okay time to call tow truck. While waiting for the Tow Truck I turn the key and the car started and idle normal. I figure okay maybe just bad gas. I went and got a oil change and put fuel in the car. I had a 1/4 of tank of gas while this happen. Car drove great for about a week and then all of sudden doing 70 on the major highway the car repeated the same situation. I have been letting the car sit for the past week and starting it and driving around the neigborhood and I notice at around 70 mph the other day it began to buck again like it did the last two times. I took it to my mechanic and it did not do it for him and he can not figure out the problem. Can some of you give me some suggestions where to look and I am going to take it to Ford Dealership. I do not want to get rid of the car because she drives great. Someone said it could be the fuel pump.