1989 Buick Skylark Car cranks, but won't start...

I just took possesion of a 1989 Buick Skylark that used to be my fathers. This car has not been driven in 5 years, and was left outside with a full tank. I put a new battery in it and tried to start it, but it just cranks and doesn't start. I sprayed some starting fluid in the air filter, and the car runs so long as that starting fluid lasts. So then I changed the fuel filter, to no avail. I am wondering if this is more likely a fuel pump issue or a fuel injector issue, or something else entirely. Thanks