Fuel Temperature Sensor 1
Indicates a problem with the fuel temperature sensor output.
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What it means (plain English)
The fuel temperature sensor monitors how hot the fuel is. If it's reading too high or too low, it can affect engine performance and emissions.
What the computer is actually seeing
The engine control unit (ECU) expects continuous voltage signals from the fuel temperature sensor, typically between 0.5V to 4.5V depending on the fuel temperature. If the reading falls outside this range, it triggers a fault.
What a healthy reading looks like
Normal fuel temperature range is usually between 40°F and 150°F (4°C to 65°C) with corresponding sensor voltages of approximately 0.5V to 4.5V.
Guided diagnostic — the DiagCoach way
Don't just throw parts at it. Walk through these in order — each step tells you whether to keep going or stop and fix what you found.
- 11. Inspect the fuel temperature sensor wiring and connectors for damage or corrosion. If any issues found, repair and retest.
- 22. Check the fuel level and quality. Replace fuel if contaminated or below normal levels.
- 33. Measure the output voltage at the fuel temperature sensor connector with a multimeter. Expected value should be between 0.5V and 4.5V. If outside this range, replace the sensor.
- 44. If the sensor is replaced and the code returns, check for ECM updates or faults in the engine control unit.
Common causes
- Faulty fuel temperature sensor
- Damaged wiring or connectors
- Poor fuel quality
- Short circuit to ground or power
- Failed ECU
Typical repair cost
$$$
Related codes
Frequently asked questions
Is it safe to drive with this code present?
It's advisable to fix this soon to avoid potential drivability issues and increased emissions.
Why does this code often pair with other SPN codes?
It's common for multiple sensors to be affected by the same issue, like wiring problems or poor fuel quality.
Will this problem return after fixing?
If the root cause is repaired (sensor, wiring), it shouldn't return unless there's another underlying issue.
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