my car has approx 175k mi of which i put on about 10k in the year ive had it. it has run great no problems no leaks of any kind it has been an exceptional car all things considered. the other night i started out to a friends for a visit. as soon as i put it in gear and took off i had an abrupt jolt as if i had run into a block of wood. got out to inspect, nothing there, tried it again. this time car gradually picked up speed to normal within about 50 yards. after driving about a half mile and stopping to visit for an hour i started back home. this time no jolt but again gardual gaining of speed. the following day around noon i went out to test it, started and proceeded to take off with no problem at all. what is the possible problem? i havent driven it since.