What kind of symptoms will a bad EGR have on a 1995 F150 (302 automatic)?

I'm trying to track down the problem of slow starting when the engine is hot. I pulled the throttle body and replaced the TPS (had a "bad tps" code), pulled the idle air control and cleaned it with carb cleaner, cleaned throttle body and the crud built up in the intake at the EGR. These things really cleaned up the idle and it runs a lot smoother now.

Truck starts fine cold but when warm it takes approx. 30 seconds to start and you have to have the gas pedal about half way down for it to start. Take your foot off the gas and turn the key and it'll spin for about 15 seconds then sound like it's trying to start but won't keep running.

What about spark plugs? These are old and I'm sure probably need replacing but I'm hesitant to right now because of the ease in starting when cold.

Thanks