backfire and rough start

i have a 1990 olds delta 88 and recently it doesnt want to start, i'll crank and crank, and finally it'll start, but it'll backfire, then it'll run normally forever, no problems while driving, and it happens only after the car has been sitting for a while, any ideas? could it be the fuel filter, or is it something with more problems?

Any trouble codes? I'm guessing that either the starter is going south or you have an issue of fuel pressure. Does the car seem to stumble when you try to accelerate?

dont know about trouble codes, we disconnected the light because it was so darn annoying, codes before then was 23, thats it, dont know about any others, sorry, as for acceleration, no problems, i'll step on the gas, and it goes, like always, cant be the starter because its practically new, but i guess things can be bad still, im not sure if thats it, doesnt seem like it to me.

Ok....the SES light is there for a reason: to tell you something is wrong with the car. Put the light back in, and pull the codes via paperclip. You do know how to do that, right?