Get the engine up to temperature but prior to starting it, check to see if there's a strong smell of fuel inside the intake. If so, an injector is likely leaking. If not, release the pressure in the fuel rail using the schrader valve where you check pressure. Be careful with where the fuel sprays... Or better yet, use a fuel pressure gauge to release the pressure; it'll have a tube just for that purpose...

When starting it that first time, turn the ignition on but wait a second for the fuel pump to repressurize the fuel rail, then try to start it. If there is no insulation around/under the injectors to keep the heat from the exhaust manifold from heating up the injectors and rail, this is likely your issue; very common problem on later-model XJs...

 

just replaced them with 12 hole injectors. Deff no insulation anywhere on the fuel rail or intake or injectors. I can see air bubbles in the fuel when I purge the fuel pressure tester when hot but none cold. Letting the jeep cool down to test this idea