2000 Civic, no mods besides Eibach springs and a DC tower brace. Engine vibrates at idle, and it definitely has something to do with the electrical systems. Car has a remote start. If you unlock the doors as the car is running, the vibration gets worse for a second. Same with flipping on the lights, radio, etc. It just started recently so I haven't had a chance to look at it yet. Bad spark plug maybe? Car seems to run fine otherwise. Alternator? Battery?