Fuel Temperature Too High
The P0168 code indicates that the engine control module (ECM) has detected a fuel temperature reading that exceeds the maximum allowable threshold, typically above 140°F (60°C). This can be caused by a faulty fuel temperature sensor, wiring issues, or excessive fuel system heat due to high ambient temperatures, fuel recirculation, or a malfunctioning fuel cooler. Prolonged high fuel temperature can lead to reduced engine performance, increased emissions, and potential fuel system damage.
1. Most Common Causes
- Faulty fuel temperature sensor
- Wiring or connector issues in the sensor circuit
- Excessive fuel system heat (e.g., from fuel recirculation or high ambient temps)
- Malfunctioning fuel cooler (if equipped)
2. Symptoms You Will Notice
- Check Engine Light illuminated
- Reduced engine performance or power
- Poor fuel economy
- Possible engine stalling or hesitation
3. Step-by-Step Diagnosis
Step 1: Use an OBD2 scanner to confirm the code and check for additional codes.
Step 2: Inspect the fuel temperature sensor and its wiring for damage, corrosion, or loose connections.
Step 3: Compare fuel temperature sensor readings with actual fuel temperature using a scan tool and thermometer.
Step 4: Test the sensor's resistance and voltage according to manufacturer specifications.
Step 5: Check for excessive fuel system heat sources, such as a stuck fuel recirculation valve or blocked fuel cooler.
4. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive long distances with this code, as high fuel temperature can cause engine performance issues and potential fuel system damage. Have it diagnosed and repaired promptly.
How much does it cost to fix?▼
The cost typically ranges from $50 to $150, including parts (fuel temperature sensor) and labor. Additional repairs may increase cost if wiring or other components are involved.
5. Commonly Affected Makes
This is a generic OBD2 code, potentially applicable to any manufacturer using this diagnostic standard.