1996 Toyota Corolla Vibrating Really Bad

Car vibrates really bad, quiets down some after a long drive.

Hi there Scotty! I'm having an issue with my Corolla. As the title states, while it's idling, it vibrates bad (worse in gear.) It's a 1.6l automatic with only 135,000 miles on it. Up until the beginning of this year, it's ran smooth as butter, then all of a sudden it started vibrating. When I'm at a stop light the steering wheel, hood and mirrors vibrate bad, but as soon as I start going it goes away. it will continue to vibrate awful even after it's warmed up, unless I go on a long drive somewhere, then it goes away almost completely. I've changed the spark plugs, all the mounts, and I'm up to date on it's oil changes. There is also no check engine light on and apart from the vibration the car drives normal. Any idea what's up? Money is tight at the moment so I'd like to try and figure it out without spending any money to diagnose it.

I would run a compression test. You might have a weak cylinder. Also with the age of the car check the harmonic balancer. Finally check for vacuum leaks. Scotty has a video on how to check for those.