Hi my name is Eric Kyttle. I have a 2000 Chevy malibu with 106K on it. The motor is very quiet and runs real smooth. The valve covers and bottom of the oil cap are covered in a yellow milky substance. The car has never come all the way to temp but pretty close. I bought all the gaskets to have the heads plained and redone but i with how well it runs i am tryin to figure out if maybe just the thermostat is bad and since the car never comes up to temp maybe the condensation in the motor never clears if it doesnt come to temp. Should i just put new head gaskets on it anyway? Thank you!