Idling issue

[Pomorza]

Hello all

I'm having an issue with my 1976 280z. Since about early November that car has a bit of an issue when idling once it warms. Best example would be I drove to the store earlier today. Parked outside went in for about twenty minutes. Came out and started the car. Car had a hard time idling and the tach jumped between 600-1000 RPM. I revved the motor and held it at 2k for about a minute or two and it evened out and drove fine the rest of the day. Any ideas as what this could be? I've replaced the temp sensor (for the ECU). Haven't done a tune up but the plugs look good (although they're champions).

Ideas?

Jan

[Pomorza]

Ok a bit more info. Drove to the store earlier today. Car ran great going there. I was in the store for ten minutes and came out. Started the car and it died twice before it "ran" very rough. IT ran rough for about five minutes and then evened out. Any ideas guy? Any?

Jan