1997 formula
New here and not a car guy at all. I bought a 1997 firebird 2 months ago to hopefully have a fun summer car. Person that sold it to me said they just replaced plugs, wires, and optispark. I didn't even know what that was at first. Car came with SES light on and seller said he did an EGR delete. I figured I would have someone replace that since it needs to pass emissions in my county.
While waiting to do that or formulate another plan to pass emissions it developed a new issue. The damn shutting off when heated up issue. I'm in Wisconsin so didn't notice the issue in March as I assume it was too cold out for the issue to surface. As it gets warmer outside, its getting worse. The car starts and runs great when cold. After its hot, between 2 and 10 minutes, depending on the outside temperature, it shuts off. It will not restart for roughly 1 minute to 10 minutes. When it restarts, it "seems" to run ok again the rest of the trip, whether its hot or not. After hours of reading I've assumed ICM, optispark, vacuum leak, fuel pump, other wire, hose getting hot and shorting.
is there anything I can check myself before taking it in and having my mechanic charge me to experiment? Could the EGR delete cause this? I had the codes checked and they all referenced EGR or o2 sensors. I cannot even sell it like this

