I just bought the Volvo yesterday and the previous owner told me about this issue. 9 times out of ten it starts and runs like a dream. Today I was getting gas and when I got back in, it would crank, but not turn over like its not getting fire. I let it sit for about 10 seconds and cranked again. After a few attempts, it started right up and drives fine. I havent had the problem again since. Any thoughts?

 

I dont know if this sounds stupid, but I talked to the guy i bought it from today and he said to leave the car running while fueling up because it would always take a few attempts before it would turn over after fueling up. Hopefully this will help with a diagnosis.