Fuel Temperature Too High
The P0168 code indicates that the engine control module (ECM) has detected the fuel temperature in the fuel rail or fuel line is excessively high, typically above 140°F (60°C). This can cause fuel vaporization, leading to poor engine performance, hard starting, and increased emissions. The fuel temperature sensor sends a voltage signal to the ECM; if the signal is out of range, the code sets.
01. Most Common Causes
- Faulty fuel temperature sensor
- Wiring or connector issues in the sensor circuit
- Excessive fuel system pressure causing overheating
- Engine overheating transferring heat to fuel system
- Clogged fuel cooler (if equipped)
02. Symptoms You Will Notice
- Check Engine Light illuminated
- Hard starting, especially when hot
- Poor fuel economy
- Engine hesitation or stalling
- Fuel odor due to vaporization
03. Step-by-Step Diagnosis
Step 1: Scan for codes and record freeze frame data.
Step 2: Visually inspect the fuel temperature sensor and wiring for damage or corrosion.
Step 3: Compare fuel temperature sensor reading with actual fuel temperature using a scan tool and thermometer.
Step 4: Check fuel pressure to ensure it's within spec; high pressure can cause overheating.
Step 5: Test sensor resistance and voltage per manufacturer specifications.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
It is not recommended to drive long distances with P0168 as high fuel temperature can cause vapor lock, engine stalling, and potential fuel system damage. Have it diagnosed promptly.
How much does it cost to fix?▼
The cost typically ranges from $50 to $150 for a fuel temperature sensor replacement, including parts and labor. Additional repairs for wiring or fuel system issues may increase the cost.