Got another problem!!

[VTracer19]

Well i gotta another problem with my awsome accord....this time my check engine light comes on when i let the car warm up a little, but it doesn't come on when i dont let it warm up...it's kinda weird...also today (this is the first time this has happened) after it has been on for like 20-30 min when i stop at a stop sign my revs go up and down without me touching the pedels....so if anyone knows how they can help me it would be greatly appreciated...peace...
p.s: i know it ant the gasket that the colent goes through cause i changed it not too long ago, i dont remember the name of it....later