What could cause a '94 Olds Achieva S v6 to run hot within 15-30 mins of driving?
Cars can not run on just water because water boils at 212 degrees, no matter what. When coolant is mixed with water 50%-50%, the boiling point gets higher. Now,for every pound of pressure this mixture is put under, the boiling point will increase 3 or 4 degrees. So a 15 pound radiator cap can mean a possible 50-60 degree added to the boiling point. Now, a defective cap can decrease your boiling point.Thus a bad cap could be your problem