Corrosion inside the distributor cap. Get a new cap and rotor.
AC/Delco
The injectors or spark plugs might be firing wrong. You should get it checked out as soon as possible.
Try checking your spark plugs & wires. Can also be caused by dirty fuel filter.
When the idle goes rough, you must idle the plugs. Else the car plugs roughly.
If you have replaced plugs and wire most likely one of your coil pack usually run about $50
I would recommend checking for codes before you do anything else.
the transmition ,is probably not adjusted to the spark plugs,or their not the right spark plugs
Well...the misfire on 1 and 3 would explain the rough idle. The misfire could be from worn plugs, wires, bad coil, or bad injectors.
I would tune it up, Plugs and wires, Factory AC Delco Cap and Rotor And change the fuel filter.
How about the ignition wires, are they original?
It may have worn spark plugs and or bad spark plug wires, time for a good tune up.
Vacuum leak. ... also try cleaning the EGR valve.