Car · Problems

Engine overheating

Overheating can destroy an engine within minutes. Stop as soon as the needle goes past halfway or the red light comes on, and never open the expansion tank when hot.

UrgencyHigh
Can I drive?No, stop
Likely causesLow coolant

Likely causes

  1. Low coolant30%
    Garage price: Coolant flush £60 – £155
  2. Stuck thermostat20%
    Garage price: Thermostat £80 – £280
  3. Cooling fan not working15%
  4. Leaking water pump15%
    Garage price: Water pump £145 – £455Garage price: Timing belt kit with water pump £315 – £780
  5. Leaking or blocked radiator10%
    Garage price: Radiator £200 – £485
  6. Head gasket10%

    Thick sweet white smoke, mayonnaise under the oil cap and coolant dropping with no visible leak.

    Garage price: Head gasket £590 – £1,560

What you can check yourself

  1. With the engine cold, check coolant sits between MIN and MAX.
  2. When hot at idle, the fan should kick in. If it never spins, suspect it or its relay.
  3. Sweet-smelling white exhaust smoke points to the head gasket.

Fault codes often linked

P0116 Engine coolant temperature range or performanceP0217 Engine over-temperature conditionP0115 Engine coolant temperature sensor circuitP0117 Engine coolant temperature sensor low inputP0118 Engine coolant temperature sensor high inputP0128 Coolant temperature below thermostat regulating temperatureP0480 Cooling fan relay 1 control circuit

Frequently asked questions

Engine overheating: what causes it?

Likely causes: low coolant (30%), stuck thermostat (20%), cooling fan not working (15%).

Can I drive?

No, stop. Urgency: high.

Indicative estimate. MecaScan cannot see your vehicle: always have a diagnosis confirmed by a professional, and never work on brakes, steering or airbags without the skills.