I had the same problem on my car. turned out to be a blown head gasket.
the no. 1 cylinder was pushing hot gasses into the coolant jacket.
The cap is on the coolant reservoir (driver's side behind the battery), not on the radiator itself as in many other vehicle makes. Mine is yellow. DO NOT remove cap if engine/coolant is hot as system is pressurized.
A broken piston ring can allow oil to get into your cooling system. A bad valve seal can also allow oil into the cooling system.
This might be the cooling fan which in today's cars is electric and runs only when needed, not continuously like the 50's and 60's vehicles. When you sit idling, with no cooling air passing over the engine, the coolant temperature rises and causes the fan to switch on. This could also happen during acceleration.
Valvoline Zerex.
When it is used as a source of water for public or private consumption.
possibly you need a better grade of gas?
No. Apparently it makes a gel.
The company that makes the all model coolant claims you can.
NO it makes no difference.
Low engine coolant--when you step on the gas water pump runs faster and is calling for more coolant--check level
head gasket failing
on any car it is usually the thermostat. or low coolant level. if level is check radiator cap it may be loose or defective. but if it is dripping coolant from under engine it is your water pump. check under your car after about 10 minutes or so after you have parked if their is coolant or if you smell coolant under the hood after you park it most likely a water pump. Do not try to drive while it is over heated it will cost you a lot of money in damage.