2000 se po300 random misfire

changed icm ,plug wires , plugs, coils. removed cat. still runs real bad. it is a 2.4 . cant think of any thing else to check. starts and runs but misses and backfires, any ideas. im spent on ideas.

It's possible you may have a vacuum leak, but I'll defer to Xero, Phantom, & the other "gurus" to help narrow it down for you.

thank you ill start checking for leaks. i did have the intake off.