What would cause misfire on 2,4,6 coil packs
disconect battery for 15 mins and try again
Look for "stuff" ozzing out below the coil pack, there is a circuit board that is potted to protect it from moisture, when it fails and then gets hot, the potting material starts to leak out and that is a clue the circuit board is bad.
Search Buick Enclave Questions
Are you a UK consumer? CarGurus now has a discussion forum in the UK.
Buick Enclave Experts