P026F
Coolant Thermostat Performance
Generic OBD-II
Common symptoms
What you'll notice
- Check and replace the coolant thermostat with a new one
- Inspect and repair any coolant leaks in the system
- Flush and refill the coolant to ensure proper flow and temperature regulation
- Inspect and clean the radiator and cooling fan for optimum performance
Common causes
Most likely first
- Malfunctioning or stuck coolant thermostat
- Insufficient coolant level in the system
- Faulty coolant temperature sensor
- Clogged or restricted radiator
- Faulty engine coolant temperature (ECT) sensor
How to diagnose & fix
Work through it in order
- Engine overheating
- Poor fuel efficiency
- Heater not working properly
- Check engine light illuminated
- Engine stalling or running rough
Read & clear P026F yourself
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