Did basic tune up on 88 Iroc. 305 TPI 5 spd, After I was done it ran terrible missing like hell at idle and missing the whole way up the revs and back fires though intake. First thought was plug wires are wrong. I checked them over and over and they are correct. I even had my brother check them and he ended up with the same result. I do recall the rotor being stuck and when i was prying it off i did hit the green round thing right under it (I know its for the timing but don't know the technical name.) and would assume this would cause all this? I even went as far as checking the timing with the electronic advance unplugged. At idle it reads 6 degrees like it should and when i rev it it reads 10~12 degrees. Any help is appreciated.