Mitsubishi

I have an asian built in the philippines (still there) 1996 mitsubishi galant with a v6 dohc engine 24 valve 3.0 liter engine 6a72 auto transmission its losing coolant thermostat working and changed. no coolant in oil, transmission fluid ok, pressure cap been changed holds pressure. have not noticed any vapor coming out of exhaust. coolant bubbles when i rev engine (radiator cap off) i suspect head gasket any ideas. if exhaust in cooling system anyway to find out what bank is causing problem? if head gasket what is part number? can buy in philippines, expensive. i am in states anyone know what one i could buy here to take to pi? it looks like it could be sku #a8100 88897. i emailed mitsubishi philippines no answer.

I had a similar problem with my tahoe. one day my sister was driving and woosh, water was spraying out of the intake manifold. turned out the intake manifold gasket was deteriorated. so i replaced the gasket and now that solved the problem.also, you could have a hole in radiator, use leek detection product or barrrs leak to plug up leak. could also be a bad heater core .