Rough running engine, trouble codes Cam and Crank issues, its time for a dealer. If under warranty, in your case extended warranty, take it to the dealer. If in fact you have no warranty you can take it to a competent shop to save a little money.
This might be a long shot, but has it been in a collision recently and repaired? I lost my crank sensor on my 92 318 Dakota after I got rear ended, after being repaired I went on a 500 mile trip and the engine stumbled a few times. Lucky for me the dealer where I went to, was open and they found the crank engine sensor to be faulty. Thankfully the engine stumbled while they the computer connected. Of coarse I never mentioned the accident, it was under warranty still.