When the temperature gets high the radiator on the driver's side starts making a popping sound. I can actually see the top of the radiator move a little bit each time that it pops. There's also a gurgling and whooshing sound coming from the upper radiator hose. The car doesn't ever overheat and you can still hear the sounds even after the car is turned off. What could be causing it to make that sound?
My car has 179472 miles.
My car has an automatic transmission.
The noise is the coolant is turning into steam due to low amount of coolant to water concentrations. The ratio should be 50% coolant to 50% distilled water or just purchase a 50/50 coolant that is already mixed. Since you say your engine is not overheating then this is the most likely cause of the popping since these engines may get over waters boiling point of 212 degrees F. Have your coolant replaced if it tests with a low boil point meaning it is not mixed correctly. Once it is drained you may want to replace the thermostat also. This is just in case it is not opening all the way or at the correct temperature. If you need help with either of these issues a certified technician from YourMechanic can come to either your home or place of business to make repairs.