Fault Code: P0168
Code Description: Fuel Temperature Too High
OBD2 code P0168 means the Engine Control Module (ECM/PCM) has detected that the fuel temperature is higher than the expected operating range. The problem may involve the fuel temperature sensor, wiring, fuel system, or an actual excessive fuel temperature condition.
What Does Code P0168 Mean?
P0168 is a generic OBD-II trouble code related to fuel temperature. The ECM monitors fuel temperature through a fuel temperature sensor or a sensor integrated into the fuel system. If the reported temperature remains above the expected limit, the ECM can store P0168 and turn on the Check Engine Light.
Where Is the Fuel Temperature Sensor Located?
The location of the fuel temperature sensor varies by vehicle. It may be installed in or near the fuel rail, fuel supply line, fuel filter assembly, fuel pump module, or another part of the fuel delivery system.
On some diesel vehicles, fuel temperature monitoring is closely associated with the fuel filter or high-pressure fuel system. On gasoline vehicles, the sensor location can be different.
Always verify the exact location using the service information for the specific year, engine, and vehicle.
Symptoms of P0168
The MIL may illuminate after the ECM detects an abnormal fuel temperature reading.
Incorrect fuel temperature information can affect fuel system calculations.
The engine may enter a protective strategy if the condition is considered severe.
Incorrect temperature data can contribute to abnormal fuel control.
Common Causes of P0168
The sensor may be reporting a temperature that is higher than the actual fuel temperature.
Open circuits, short circuits, melted insulation, or wiring near hot components can affect the sensor signal.
Corrosion, loose terminals, moisture, or poor electrical contact can create an incorrect temperature signal.
The fuel may actually be hotter than the expected operating range because of a fuel-system or cooling-related problem.
Fuel circulation, return-flow, pressure, or heat-transfer problems can contribute to abnormal fuel temperature.
P0168 Diagnosis
Start by checking the vehicle's freeze-frame data and live fuel temperature reading with an OBD2 scan tool. Compare the reported fuel temperature with the actual conditions.
If the engine is cold but the scan tool reports an extremely high fuel temperature, suspect the sensor or its circuit before replacing other fuel-system components.
Inspect the sensor connector and wiring for corrosion, damaged terminals, broken wires, melted insulation, or contact with hot exhaust components.
How to Fix P0168
Repair damaged, shorted, open, or heat-damaged wiring.
Clean corrosion and repair loose or damaged terminals.
Compare sensor resistance or signal voltage with the manufacturer's specifications.
Determine whether the fuel is actually overheating or whether the sensor is giving a false reading.
After the repair, clear P0168 and perform a road test to confirm that the code does not return.
Common Repair Cost for P0168
The repair cost for P0168 varies considerably depending on the vehicle and the actual cause of the fault.
These are general estimates only. Labor rates, vehicle design, sensor location, and OEM parts prices can significantly change the final repair cost.
Common Repair Mistakes
Do not replace the fuel temperature sensor before checking its wiring, connector, and actual temperature reading.
Heat-damaged wiring around the engine and fuel system can produce the same symptoms as a failed sensor.
Always verify the correct sensor for the exact vehicle, engine, and fuel system.
Clearing P0168 without finding the cause usually results in the code returning.
Manufacturer-Specific Notes for P0168
The generic meaning of P0168 is related to excessively high fuel temperature, but the sensor location, diagnostic strategy, and common failure points can differ between manufacturers.
Chevrolet and GMC
On some Chevrolet and GMC vehicles, P0168 can be associated with fuel temperature monitoring in the fuel system. Check the sensor circuit, connector, wiring, and live-data temperature before replacing components.
Honda
Honda vehicles may use fuel temperature information as part of fuel-system calculations. If P0168 is present, verify the sensor signal and compare the scan-tool reading with actual fuel temperature.
Nissan
On Nissan vehicles, inspect the fuel temperature sensor circuit and connector carefully. Vehicle-specific service information should be used to identify the exact sensor location and expected signal values.
Jeep
On Jeep vehicles, the exact implementation of fuel temperature monitoring varies by engine and model. Check the wiring, connector, sensor signal, and related fuel-system data before replacing the sensor.
Diesel Engines
P0168 is not exclusively a diesel code. However, it can appear on diesel applications because many modern diesel fuel systems actively monitor fuel temperature. Diesel systems may have the fuel temperature sensor integrated into the fuel filter, fuel rail, fuel supply system, or another fuel-system component depending on the engine.
Can You Drive With P0168?
Short-distance driving may be possible if the vehicle is running normally and there are no additional fuel-system or overheating symptoms. However, P0168 should not be ignored because an incorrect fuel temperature reading or genuinely excessive fuel temperature can affect engine operation and fuel-system control.
Frequently Asked Questions About P0168
What does code P0168 mean?
P0168 means the ECM/PCM has detected fuel temperature above the expected operating range.
How do I fix P0168?
Start by checking the fuel temperature sensor, wiring, connector, and live-data reading. If the reported temperature is incorrect, test the sensor and circuit. If the temperature is genuinely high, diagnose the fuel-system cause.
Where is the fuel temperature sensor located?
Its location depends on the vehicle. It may be located near the fuel rail, fuel line, fuel filter, fuel pump module, or another fuel-system component.
Can a bad fuel temperature sensor cause P0168?
Yes. A faulty sensor can incorrectly report an excessively high fuel temperature and trigger P0168.
Is P0168 serious?
The severity depends on the cause. A faulty sensor or wiring problem may be relatively simple to repair, while an actual fuel-temperature or fuel-system problem may require further diagnosis.
Does P0168 mean the fuel is actually too hot?
Not necessarily. The code can be caused by an incorrect sensor signal, wiring fault, or connector problem. Actual fuel temperature should be verified before assuming the fuel is overheating.
Related OBD2 Codes
O2 Sensor Circuit Slow Response – Bank 2 Sensor 2
Fuel Temperature Sensor A Circuit
Fuel Temperature Sensor A Circuit Range/Performance
Fuel Temperature Sensor A Circuit Low
Fuel Temperature Sensor A Circuit High
Final Result
P0168 indicates that the ECM/PCM has detected fuel temperature above the expected range. The best approach is to verify the actual fuel temperature, inspect the fuel temperature sensor and its wiring, and then diagnose the fuel system if the temperature is genuinely excessive. Because sensor location and diagnostic procedures vary by vehicle, always confirm the specifications for the exact make, model, engine, and year.