I had a case of bad gas, and just for clarification no it's not the kind after eating Taco Bell at 3am, in my car. I put some gas in my car right in the transition of winter to spring/summer and it ran like crap until I went through that tank of fuel and then it ran fine again. With the crappy gas that we have today, if a car sits too long it isn't good a good thing, especially in a carbureted car. I'd start by checking both of your fuel filters, you should have one right by your gas tank and one between your fuel pump and carburetor. Check to see if there's a bunch of crap in there and if you don't have a fuel filter between your fuel pump and carburetor, now would be a good time to install one. I also only use premium fuel now. IMO the extra $.10-.20 per gallon seems like a small price to pay compared to having costly engine issues because of getting cheap gas.