The car has around 140,000 miles 3.8 & automatic. From day one of us buying the car it's had a vibration. The tires were in bad condition and I thought that was the problem but it wasn't it seems to be when the trans is shifting. At this point it's had new spark plugs & wires, air filter, Trans has been serviced with new filter & fluid. The car broke down about a year ago now and I had to put a new fuel pump in it. The fuel pump was changed a new fuel filter and the gasket for the filler neck and tank plus the tank was cleaned out. After the fuel pump change I noticed the car would surge or have a skipping intermittently going up a hill at times now the skipping or surge is happening more often and not only going up a hill. When I refer to a hill it's a stretch of road with a decent incline. Engine light hasn't come on. The fuel pump came from Advance/ Car Quest auto parts if my memory is working right the fuel pump was a Car Quest brand. Any advice for things to check would be great. This is my daughters car and she said it has got worse in the last week but she waited till today to tell me. And I have to go out of town till Sunday or Monday. My lean too is something with the fuel system. I want to add fuel level don't seem to effect it if it's a 1/4 tank or full tank.