Honda Civic 98 Some "minor" issues

Honda Civic 1998 LX Automatic 1.6 L. 145k. I had an engine installed a while back with only 45k miles on it. I recently had the car at a body shop to do some repairs to the front.
1st: My car idles in park at about 1500 rpms. Sometimes it jumps back and forth.
2nd: If I just tap the acceleration the car revs back and forthand the rps jump but it drives fine when I accelerate it more.
3rd: This started happening but somethime when I am at a red light for more then 30 seconds, when I push the gas, it revs but it takes about 3 seconds to start moving.