I was driving home from work the other day and had just shifted into 5th gear(i have a manual trans). I was approaching another car from behind, and let off the gas until I could pass. There was a bump from the engine or trans when I let off the gas. Then, when I pushed the gas pedal again, there was another more violent bump. It felt like the engine/trans was rocking front to back, but that is hard to confirm since it only happens when driving. I have also noticed that when I let off the gas and turn a corner in second gear, the car lurches. It does not do this if I accelerate through the corner. Any ideas what this might be? I'm thinking motor or trans mounts, but might this also be a clutch problem? The previous owner replaced the clutch before I bought it(15,000 miles ago) and I am easy on the clutch, so I don't think it is the clutch, but just thought I'd ask. Thanks.

 

Loose engine mounts sounds like a good idea. Grab the valve cover & shake the engine around to checkthe mounts.