I have a 2004 XJR. I recently noticed under hard acceleration (well, not pedal to the floor but not driving like an an old lady either) that the hood will lift up about an inch on the the drivers side, closest to me and then drop back down. This was not happening before and now does. It will not happen if the car is moving say 30 MPH and then I pull onto a highway and quickly move to 80 MPH, only if the car is stopped and accelerates quickly.

From googling around I assume its a broken engine mount, I saw no leaking fluid however, and the idle isn't rough. I can tell the engine is on but its not shaking my teeth out or anything. The car runs fine, and has no codes and is still fast but doesn't FEEL quite as fast as it used to be (could just be me)

So would this be an engine mount or something else? How could I see? How many engine mounts are there? (I'd assume 4) If my guess is correct, how much is this going to be to fix? That is a video I have found on the problem but mine is nowhere near that bad.