* Low coolant level: Check your coolant reservoir. If it's low, you have a leak somewhere in the system.
* Coolant leak: Look for leaks around the radiator, hoses, water pump, thermostat housing, and engine block.
* Faulty radiator cap: A faulty radiator cap won't maintain proper pressure in the cooling system.
* Faulty thermostat: A stuck-open thermostat will prevent the engine from reaching operating temperature, leading to lower pressure.
* Head gasket failure (serious): In more severe cases, a blown head gasket can allow coolant to leak into the cylinders or oil, leading to low coolant pressure.
A soft upper radiator hose when the engine is hot is a warning sign that needs immediate attention. Driving with a low-pressure cooling system can lead to engine overheating, which can cause severe and costly engine damage. Have your vehicle inspected by a qualified mechanic as soon as possible.
