2002 buick lesabre intake manifold change out

we just replaced the intake manifold and also put on new spark plug wires and plugs. now the engine is missing but only after it warms up. i double checked all the wires and connections and they looked good. is there something obvious that i should look at since it is still doing it?

The most obvious thing to think of is that something went not quite right with the manifold install. Did you follow the exact factory torque specs and procedures? The engine runs richer when cold so if you ended up with a small manifold leak it could get masked when cold but show when warm. You can check for leaks with some carb cleaner or an unlit propane torch or something like that.

Are there any codes showing (check engine light)?

no check engine light came on. followed the procedure and torqued to spec. i will try checking for leaks tonight.