#2 cylinder misfire
 

Hi everyone, new here!
My Girlfriend has a 1997 Mitsubishi Galant with 65,000 original miles on it, and in sweet condition.
The car started to rough idle at stop lights last week, so she asked me to look at it. First: the only code is P0302 (misfire #2). I have changed the plugs, wires, cap and rotor. Still misfire #2. So I then dug deeper. Changed #2 injector even though it was within ohms specks (15.7 and all were) in case it was plugged. Then I checked the continuity of the wire all the way to the connector by the radio (all good), so I changed the injector plug to insure contacts. Better but still occasional rough idle, and misfire.
The idle speed is adjusting the rpm's to 900, and when it run above idle the car has great power, and very smooth. A mechanic told me it could be the brain skipping the neg. impulse of #2 at an idle. Before I change out other parts....I figured I ask you folks if you have had the same issue with a cylinder pulse not registering.
Thank you, Mr. puzzled! LOL

Thankyou for a literate and intelligent post. Unfortunately once you put a computer between me and an engine my only thought is to use a hammer. I hope one of the new-fangled folk is along to help you out soon, but might, in my ignorance, suggest cam sensor/s, distributor?

Thank you Akzle,
I thought of the cam sensor, but it reads it's position for each revolution or the other 3 wouldn't fire. Plus the car run perfect at any and all RPM's except for the idle. A true kick in the teeth!