I have a 2000 Cougar and every once in a while when I'm driving it will act like it's running out of gas, even if I have a full tank. Sometimes it leaks a ton of coolant when I park so that I have to refill it, but that doesn't happen every time I drive, more like 1 in 12. Someone suggested that it might be my radiator cap? The leak is on the drivers side somewhere but I can't tell where it's coming from. I usually find that it happens when I'm in a hurry and really pushing my car to get somewhere quickly, or if I have to deal with a lot of traffic. Any suggestions?