I also wonder after your email I appreciate so much... where if my head gasket leaks slowly, then can I drive it a few more months? A local mechanic kept me coming back and I spent almost $2,000 on it last spring. If it leaks only a little, then also could it suddenly have a major blow and I'd be stranded and have to tow it? It has all new timing belt OEM $196 kit installed, tranny flushed and new filter, and differentials (AWD), new rear brake calipers and all new pads, 4 almost new tires (cost $450 gift from my sister), or sell it for parts and if I do how much would you ask for it? Do you recommend any head gasket tester kit over another? I see Napa has one that doesn't have that double decker design like in your video. Is that double decker or double vial design best? Thanks for all you do.