bad head gasket go to auto store borrow cooling presser check
if the coolant looks like a strawberry milkshake, check the Transmission Fluid, the transmission oil cooler inside the radiator is bad.
if the coolant looks like a chocolate milkshake, probably head gasket as said above.
It means that your engine oil is mixing in with your radiator fluid. You probably have water in your oil too. I would take it in and have it fixed.
Probably any normal thing like not enough Radiator Fluid or something is wrong with your radiator or a head gasket leak could cause the radiator fluid loss. Does this Help?
Unless your radiator has a leak, the radiator fluid stays in the radiator.
Only if it is allowing Fluid to escape. Does the radiator and heater core have enough fluid to circulate. If not you will not have heat.
1 simple cause may be a damage radiator cap or simply low fluid.
radiator fluid
Well a possibility is a problem with the radiator, either it needs to be fixed, replaced, or has no radiator fluid in it to cool the engine.
There are a number of reasons: 1. Faulty thermostat can cause the fluid to overheat and expand; thus causing the fluid to vent from the overflow pipe. 2. A punctured radiator hose, or a broken seal can cause loss of fluid. 3. Damaged radiator core.
broken radiator
It could be your thermostat how is the fluid in your radiator?
Thermostat stuck closed.
The heater core is a radiator in the car, warmed with coolant from the engine. When you put the Air-con on hot, and turn the fan on, the air is blown over it to warm the air (and you in the car) up. As it contains radiator fluid, it can cause the level to drop if it leaks. Check the carpets in the car to see if they are wet with radiator fluid, or to see if the car leaves a puddle of fluid coming out of the air con condensation drain.