Engine overheating — what to do and what are the causes?

Engine overheating must not be ignored — it can end with a damaged head gasket or cylinder head. The most common causes are a coolant leak or a faulty fan, thermostat or water pump.

Most common variants and causes

Coolant level keeps dropping

Avoid driving — call us
  • Leaking hose, radiator or water pump
  • Faulty expansion tank cap
  • Head gasket (coolant in oil, white exhaust smoke)

Driving on may be unsafe or cause serious damage. Call us — we’ll advise whether to drive in or use a tow truck.

First step: Coolant replacement — from 200 złEngine repair →Book a diagnosis →

Temperature rises in traffic

Check within a few days
  • Radiator fan or its sensor
  • Clogged radiator (outside or inside)
  • Thermostat

The fault can get worse and more expensive. Drive carefully and book a diagnosis.

First step: Computer diagnostics — from 100 złMechanics & service →Book a diagnosis →

What you can check yourself

  1. When the temperature gauge climbs, pull over safely and switch off the engine.
  2. Don’t open a hot coolant reservoir — the coolant is under pressure and can scald you.
  3. Once it has cooled down, check the coolant level and whether there’s a coloured puddle under the car.
  4. Check whether the radiator fan switches on when the car is stationary.

How we check it in the workshop

We pressure-test the cooling system for leaks, check the fan, thermostat and water pump and, if a head gasket failure is suspected, test for exhaust gases in the coolant.

This is guidance only, not a diagnosis. We’ll find the exact cause at our workshop in Bielany — you approve the quote before any work starts.

Frequently asked questions

Can I drive to the workshop with an overheated engine?

If the temperature is in the red zone — no. Give us a call and we’ll advise whether you can get here safely or should call a tow truck.

Can I top up with water instead of coolant?

As an emergency measure to get here — yes. Afterwards the system must be filled with the proper coolant, otherwise it may freeze in winter.

How do I know it’s the head gasket?

Typical signs are coolant loss with no visible leak, white smoke from the exhaust and “mayonnaise” in the oil under the filler cap. A workshop test confirms it.