Something weird happend to my car today
 

So my 4cyl 95 camry has idled rough while at idle and really rough when the AC is on, it has done this since I bought it. It was so bad my windows would shake and the change in my ash tray would rattle so bad people on the phone could hear it. Since I have bought it I took apart the TB and everything that could be cleaned was clean, I replaced everything I could, and it never went away, I just figured motor mounts and never bothered. Well today when I was in reverse backing up and, you know how sometimes you put it into drive while still moving back just a little, well I did this and as soon as I did and put it in drive of course I heard a little bump, then wolla, my car stop idling rough. It was idling so smooth I thought the car died but it didnt. Now my car idles like a brand new car, its weird. I can crank the AC on full blast at a stop light and it idles like silk. The only think I can think of is that something may have been stuck under the car between the frame and mount that was making it shake, this has happened on my jeep before. But now when its cold I go from neutral to drive its a little rough, or neutral to reverse its rough, but the car idles amazing now, I am at a loss, what do you guys think? And what about the hitting into drive or reverse from park or neutral rough now, this is weird. It runs fine, and shifts fine when driving it, just now has the shifting into drive or reverse thing, and it doesnt idle rough anymore. Any thoughts?

4 cylinders before 1996 where known to shake if the idle became too low.

Have you cleaned the IAC valve?

When the AC compressor turns on the idle is supposed to increase to compensate for the load, was this happening?

The engine mounts, dog bone and front hydraulic can fail resulting in increased vibration at idle.

I dont mean to be mean but did you fully read my post? I have cleaned and replaced everything, along with a brand new AIC, EGR, ect. I figured it was the mounts and haven't bothered to replace them, except the dog bone. Then the other day going from reverse to drive which I did a little too soon cause my car was still moving backwards just a little it jerked and the shaking and rough idle went away completely its gone. I did a diagnostic on the tranny and got a err 63 which is sift soleniod #2, I reset the ecm and got rid of the code and have driven it 100 miles and it hasnt come back. My guess is it was stuck or shorted and me popping it into drive had something to do with it. Weird