let's talk hypothetically...what are the chances it's a head gasket? and if so, what kind of expense are we talking about? is this a DIY proposition or no? what are the potential pitfalls/problems inherent to this repair? I do work in a multi-line luxury dealership-affiliated bodyshop so I suppose I could lean on one of the mechanics to do the repair as a favor if I have to...

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2002 Ford ZX2
2 x 2013 Honda Civics