Bad Idle

I just bought a 87 Z with a 350 4bbl I believe, and I am having problems with it Idleing, and when I am running it want to surge, the guy I bought if from replaced the good stuff, fuel pump ox sens, and tune up but it still wants to surge, he says it has been sittingm you know the story. Also it dont seem to have the power it needs, it has 100,000 on it but when running it sounds good no pings or pongs, and also it likes to run so much it dont want to shut off, Deseling I think its called. Help!

Thanks

IW

Check to make sure it is getting good spark