I have a 1989 Mitsubishi mirage 1.5l 4cylinder, I found out that its misfireing on #2 and #3 cylinders and has a rough idle what could be the problem

 

My guess would be some type of gasket. I am NO type of mechanic but I just replaced the intake manifold gasket on my daughter's car and it solved the problem. Are you leaking any oil from the top area of the engine? This wasn't an easy repair but it wasn't the most difficult thing I have ever had to do.