What it means
The fuel temperature sensor A signal is within electrical limits but inconsistent with plausibility checks (e.g. doesn't change with engine warmup, disagrees with ambient temperature).
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
Fuel Temperature sensor A supplies a reading that the engine control module checks against expected temperature behaviour. This code sets when the electrical signal is present but sensor A’s value does not change or agree plausibly with operating conditions, such as during warm-up.
Common causes
Most likely first.
- Sensor reading drifted
- Sensor stuck at fixed value
Symptoms
- Check engine light on
- Hard starting or rough running
- Reduced engine performance
- Fuel economy may worsen
How to diagnose it
- Review freeze-frame data and compare live sensor A fuel temperature with ambient temperature and any available fuel temperature sensor B reading.
- After a cold soak, check whether sensor A begins near a plausible ambient-related value, using the vehicle’s specified comparison method.
- Monitor sensor A data as the engine and fuel system warm; look for a reading that stays fixed or changes implausibly.
- Inspect sensor A’s connector and wiring for corrosion, looseness, heat damage, or chafing that could distort the signal.
- If the circuit checks out, test fuel temperature sensor A against the manufacturer’s specification and replace it if it is stuck or drifting.
Common fixes
- Repair a loose or corroded sensor A connector or terminal.
- Repair damaged wiring in the fuel temperature sensor A circuit.
- Replace fuel temperature sensor A if its signal remains stuck or implausible with a sound circuit.
- Clear the code and confirm the reading responds plausibly under the conditions that previously set it.
Can I keep driving?
If the vehicle runs normally, cautious driving to arrange diagnosis is generally reasonable. If it becomes hard to start, runs roughly, or loses power, avoid extended or strenuous trips because incorrect fuel-temperature input may affect engine control.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.