Well, I think you are on the right track. Excessive white smoke from the exhaust is a sign of coolant being burnt in your vehicle's engine's combustion chambers, and your spark plugs sound like they either oil fouled or carbon fouled. Oil fouled spark plugs, again, would point towards a blown head gasket[s]. The only "pour in" head gasket sealer I would recommend, would be Blue Devil, which is available at any auto parts store. It costs a little more, but it has a higher success rate. I would recommend replacing the head gaskets, instead of using a head gasket sealer, though. In the diagrams down below I have included a diagram explaining how to read spark plugs, and the instructions for the removal and installation of the cylinder head gaskets on your vehicle, as well as the Original Equipment Manufacturer[OEM] part number for your reference as well. Please go through these guides and get back to us with how everything turns out.
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Friday, January 10th, 2020 AT 4:53 PM