'93 Sentra XE starting rough

I bought this car about a month ago, changed the air filter, plugs, wires, cap, and rotor. This didn't help the rough start, but my gas mileage is back in the 30's where it belongs. I thought the rough start could be being caused by the battery ground, since it was pretty bad, and my new radio had been having grounding issues, so I changed it. The radio is better, but it didn't help the startup.

The car turns over for a good 5-10 seconds before starting, stumbles for a few seconds, and then runs just fine. I have pleny of power, great fuel economy, etc. It does this whether it is hot or cold. If I shut it off and start it right back up, its fine, but after five minutes or more, it will hesitate again. Mileage is 115k.

fuel pump

I was afraid someone would say that. Is there any chance that the filter is just really clogged up? It looks original from what I can see. When I first turn the key in the morning I don't hear an excessively long hum from the pump.

do the filter. its cheap enough, easy enough, and should be done anyways.

I guess I'll do that this weekend. If it doesn't help, I guess I'll drop the tank and change the pump. Thanks for the help guys.