My car does not idle correctlly on 1994 Toyota Supra

I had my old supra motor replaced with a less used engine from Japan. Ever since the replacement the engine seems like it need to be tuned up or something. It does not idle correctly and the car sometimes seems like it is shivering while it is in park. What can I do about this problem?

Asked by for the 1994 Toyota Supra
Take the car to a Toyota specialist and get it fixed. Or take it to whoever installed it and have him fix it, unless you don't trust him anymore. He shouldn't have let the car go if it didn't run right.
If you want to find a specialist, here's a directory link for you: