P026F
Coolant Thermostat Performance
Thermostat does not regulate coolant temperature in the expected range. Often stuck open (slow warmup) or stuck closed (overheat).
Thermostat does not regulate coolant temperature in the expected range. Often stuck open (slow warmup) or stuck closed (overheat).
Common causes
- high
Thermostat stuck
One of the most commonly reported causes for this code — check this first.
Typical part cost: $70-440
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First things to check
- 1Confirm the code with a scan tool and check for additional related codes.
- 2Inspect the relevant sensors, wiring, and connectors for damage or corrosion.
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Related codes
See related trouble codes
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Frequently asked questions
What does P026F mean?
P026F means "Coolant Thermostat Performance". It is a generic OBD-II code that points to a fault in the fuel & air metering (injector circuit).
What are the most common causes of P026F?
thermostat stuck — these are the most commonly reported causes. Verify with a proper diagnosis before replacing parts, or use the Wrenchify app for a vehicle-specific diagnosis.
Can I keep driving with this code?
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical. Use the Wrenchify app for a full diagnosis specific to your vehicle.
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