Fuel Temperature Sensor A Circuit Malfunction
What does P0180 mean?
The P0180 code means the vehicle's onboard diagnostic system has detected: Fuel Temperature Sensor A Circuit Malfunction. This is a low severity code.
Common Symptoms
- Check Engine Light on
- Slightly reduced fuel economy
- No major drivability symptoms
- Engine may run slightly rich or lean
- Possible hard starting in extreme temperatures
Probable Causes (Ranked by Likelihood)
- Failed fuel temperature sensor Very High
- Wiring issue -- open or short in the sensor circuit High
- Corroded or damaged connector Moderate
- Poor ground connection for the sensor Moderate
- PCM internal fault Low
Step-by-Step Diagnostic Procedure
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Read the fuel temperature on a scan tool with the engine cold (sitting overnight). It should be within 10 degrees F of ambient temperature. A reading of -40 degrees F or 300+ degrees F indicates a circuit fault.
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Disconnect the fuel temperature sensor and measure its resistance. It should follow a temperature-resistance curve similar to a coolant temp sensor (2,000-3,000 ohms at 68 degrees F).
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Check the 5V reference voltage and ground at the sensor connector with the sensor disconnected.
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Inspect the wiring for damage, especially near the fuel tank and along the fuel line routing.
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Check the connector for corrosion or fuel contamination.
Frequently Asked Questions
Can I drive with code P0180?
Yes, you can drive normally. The PCM uses fuel temperature data for minor fuel delivery adjustments. Without it, the engine will still run but may be slightly less efficient.
What does the fuel temperature sensor do?
The fuel temperature sensor measures the temperature of the fuel in the fuel rail or fuel line. The PCM uses this data to fine-tune fuel injection volume since fuel density changes with temperature -- hot fuel is less dense and requires more volume.
Is this code more common on diesel engines?
Yes. Diesel engines rely more heavily on fuel temperature data because diesel fuel density varies more with temperature than gasoline. The fuel temperature sensor is critical for accurate fuel metering on diesels.