leaking intake gasket. gm is notorious for them
Cause you ask about it on Answers.com
the most common cause would be a stuck closed thermostat.
A blown head gasket.
would a cracked blocked cause a car to bubble antifreeze inside the reservoir of a 97 ford taurus ?
cracked head or bad gasket
If it is motor oil in the anti freeze, then it is either a cracked head, cracked engine block, or a head gasket blown. If it is transmission fluid in your antifreeze, then the radiator is leaking from the transmission cooler ----- although usually that would cause antifreeze to be in your transmission fluid.
You probably used the wrong type of antifreeze. You should use the type for aluminum heads.
if it smells like antifreeze inside the cockpit then your problem is the heatercore, since you can't see it.
Headgasket!
Mixing the new red antifreeze with the green can cause it to look rusty and will form a sludge. If someone is topping off your antifreeze recovery tank during oil changes with the wrong product could be one cause.
Head gasket or cracked head. Mo
check antifreeze level