So...that is a "theft cancellation" feature!

I imagine you could spend a grand paying a shop to change a head gasket, but it is on the steep side. I'd say $600-$700 is more like it. It isn't terribly difficult....do you have the means to DIY?

Do you have any insurance coverage on this? You might be able to turn it in as they ruined the engine. I did that for a Caprice that got stolen from me, they lurched the engine, insurance covered it.