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Probably either the head gasket or the valve gaskets leaking into the spark plugs. Need to have diag. and find out which.
Get the check engine code read at a parts store for free. Then, post the results on here.
Check transmission fluid level.
P0170 = Fuel trim malfunction probably MAF sensor... Po171 = system too lean bank 1....P2195 = o2 sensor stuck lean bank 1 sensor 1....could just be a bad o2 sensor. All these things are covered under warranty for a vechicle as new as yours. Take to dealer.
Agree with Greg, get thread repl and should solve the prob.
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Need plug tubes and valve cover gaskets replaced. Agree with wetry.
Take to dealer and see if they can recode keys to your vechicle. Unless the actual ignition is bad then refer to answer #1.
Most likely one of the door sensors is not functioning properly. This makes the vechicle sense that a door is open and the interior lights come on like when you exit the vechicle. Otherwise you have a short somewhere else in the system.
This video should help you http://www.youtube.com/watch?v=D65x8G1f6AI