P0126
Insufficient Coolant Temperature for Stable Operation
Generic code
Fuel and Air Metering
High severity
Moderate repair
Free on OBD DashX
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What P0126 means
- The fault code P0126 indicates that the engine coolant temperature is below the thermostat regulating temperature. This may cause the engine to run poorly or not at all.
Possible symptoms
- Illuminated check engine light
- Poor engine performance
- Decreased fuel efficiency
- Overheating engine
Possible causes
- Faulty thermostat
- Low coolant level
- Malfunctioning engine coolant temperature sensor
- Faulty engine control module (ECM)
Related parts
- Engine Coolant Temperature Sensor: The coolant temperature sensor measures the temperature of the engine coolant. Problems lead to engine overheating
Possible solutions
- Replace the faulty thermostat
- Check and refill the coolant level
- Replace the malfunctioning engine coolant temperature sensor
- Replace the engine control module (ECM) if necessary
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P0126 on OBD DashX
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