I have a 2012 Chevy Sonic manual and experiencing jerkiness when decelerating and in gear. It's probably been like this for 5+ years. It does not happen if I shift to neutral and coast, and it's more apparent at low speeds (1st to 3rd gear) although it does still happen at higher gears and speeds. I replaced the engine mounts and trans mount a while back and made no difference. Any ideas what is causing this and the fix? Thanks in advance