What usually causes it
- A thermostat (the valve that controls engine temperature) stuck open, so the engine never gets warm enough
- A failing coolant temperature sensor
- Low coolant
- A loose plug or damaged wiring at the sensor
P0125Starts at: Get it checked this week
Engine is slow to warm up for normal fuel control
The engine coolant did not warm up in the time the computer expects. The computer then keeps adding extra fuel and may be reading the wrong temperature.
Check this first
Only when the engine is fully cool, look at the coolant level in the plastic tank. Never open the radiator cap on a hot engine.
What to watch for
- The heater blowing weak or cold air
- The temperature gauge never reaching the middle, or suddenly shooting up
- Poor gas mileage
Can I keep driving?
We rate P0125 as Get it checked this week. It is not an emergency yet, but it can get worse. If the light starts flashing, stop driving soon.
Quick answers about P0125
What does P0125 mean?
Engine is slow to warm up for normal fuel control. The engine coolant did not warm up in the time the computer expects. The computer then keeps adding extra fuel and may be reading the wrong temperature.
Can I keep driving with P0125?
We rate P0125 as Get it checked this week. It is not an emergency yet, but it can get worse. If the light starts flashing, stop driving soon.
What usually causes P0125?
The most common causes, in order: A thermostat (the valve that controls engine temperature) stuck open, so the engine never gets warm enough; A failing coolant temperature sensor; Low coolant; A loose plug or damaged wiring at the sensor.
Estimates only. A mechanic should confirm. The same code can mean slightly different things on different cars; the app explains it for your exact year, make, model and mileage.