DoDo1975,
My car starting running poor at idle too. Once moving, it seemed fine. I cleaned my MAF and K&N filter. That didn't help. The shop tested the injectors and found #2 was bad. The coilpacks and plugs were fine.
Your car needs a leak down test. It will show if the piston or valves have a problem. My pistons were fine, but an exhaust valve on #2 was burnt and was not closing.
I am beginning to think that on the older cars the injectors need to be removed, cleaned, and flow tested. If one becomes clogged, the cylinder will run lean and the valves will be damaged.