What causes the Volvo XC60 engine to overheat and reduce speed?

[FelicityDella]

Cooling system leakage or insufficient coolant, issues with the water temperature gauge, excessive scale in the cooling system, problems with the radiator fan, loose or broken fan belt, damaged water pump. The thermostat is damaged in the main valve position. The engine operates under prolonged overload. Vehicle temperatures generally range between 75-95 degrees. More engine information is as follows: 1. Introduction: An engine (Engine) is a machine capable of converting other forms of energy into mechanical energy, including internal combustion engines (reciprocating piston engines), external combustion engines (Stirling engines, steam engines, etc.), jet engines, electric motors, etc. For example, internal combustion engines typically convert chemical energy into mechanical energy. 2. Kinetic energy: The engine provides the necessary kinetic energy for the vehicle, including the kinetic energy required to drive hydraulics and generators. A car consists of four main components: the engine, chassis, body, and electrical system, with the engine supplying the necessary kinetic energy, including that required to drive hydraulics and generators.

[LaAlejandro]

I've driven the XC60 a few times and found that engine overheating and power reduction usually occur in these situations: either the coolant is insufficient or deteriorated—I've personally seen deteriorated green coolant clump up and block the pipes; or the radiator is clogged with insect remains or willow catkins—some owners resolved the issue after cleaning the radiator; it could also be a water pump failure—last time, a friend's car had a seized water pump bearing, which stopped circulating the coolant; another common issue is the electric fan connector getting short-circuited due to water ingress, directly causing the fan to stop working; a stuck thermostat is also troublesome, making the engine act like a pressure cooker. Volvo has an automatic protection program that forcibly reduces power when the temperature gets too high—though frustrating, it effectively prevents engine seizure. If this happens, pull over safely immediately, and never open the radiator cap right away—scorching steam spraying out is no joke.

[OGavin]

During summer, I repaired two XC60 models with overheating issues. The main causes can be categorized into hardware defects and software faults. On the hardware side, the most common issues are coolant leaks from the radiator or aging cooling pipes, with aluminum radiator seams being particularly prone to cracking. Turbocharger return pipe leaks are also a frequent problem. On the software side, most cases involve false readings from the coolant temperature sensor or erratic behavior from the cooling fan control module, which can only be detected by reading real-time data streams with a diagnostic computer. Additionally, the pressure relief valve in Volvo's expansion tank cap can fail, leading to insufficient system pressure and rapid temperature spikes. A crucial reminder: Nordic cars must use OEM-approved coolant, as standard blue antifreeze can form silicate deposits that clog the radiator.

[VanWalker]

High-temperature power reduction is essentially a forced protection mechanism by the ECU. When the engine exceeds 115°C, the XC60's engine control unit actively limits torque output. I recommend troubleshooting in three steps: First, check if the coolant level is between MIN and MAX, and squeeze the hoses to see if they feel hard—this indicates trapped air. Next, listen to see if the fan is running; if the fan doesn’t run at full speed even with the AC at maximum airflow, it’s likely a resistor or module issue. Finally, inspect the coolant circulation—if there’s a significant temperature difference between the upper and lower radiator hoses after startup, it means the thermostat isn’t opening. Volvo’s newer engines have extremely high demands on cooling efficiency. There have been cases where excessive tilt of the AC condenser blocked airflow.

[NolanLynn]

My colleague's 2020 XC60 T8 had this issue addressed just last week. Two key findings emerged: first, oxidation of the coolant reservoir sensor pins near the charging port caused the system to falsely detect low fluid levels; second, abnormal noise from the electric water pump bearings resulted in insufficient flow, particularly noticeable during start-stop operation. Volvo's design is quite unique—the turbo intercooler and radiator share the same fan, and a loose fan belt can directly lead to dual-system cooling failure. The newer models now use electric water pumps, allowing coolant circulation to continue cooling the engine even after shutdown. If you encounter deceleration issues, don't panic—turning off the AC and switching to heater mode can actually help dissipate engine heat.