E30 Misfire

Hey guys I'm new in this:



I Have a 1986 325e and lately its giving me like a misfire.

Is not constant so it comes and goes from time to time. I been watching the rpms and its not attached to any specific.

I also check the resistance in the spark plug cable and it's constant, the car spark are new.

I change the fuel filter last summer, and I been using Shell gasoline since.

I've change the oil 4 times in the past year.



A friend of mine told me it can be the AFM.



Any help will be great..

Thanks in Advance :)

E30 Misfire