P1168 Fuel Select Switch Malfunction
The P1168 code indicates a malfunction in the fuel select switch, which allows the driver to manually choose the fuel type in bi-fuel vehicles (gasoline/E85 ethanol or gasoline/CNG). The Engine Control Module (ECM) detects that the switch signal does not match the expected configuration, is out of range, or shows a logical inconsistency with the vehicle's operating conditions. In Nissan/Infiniti vehicles, this system is critical for proper air-fuel mixture and ignition timing adjustment when using alternative fuels.
01. Most Common Causes
- Faulty or worn fuel select switch
- Open, shorted, or high-resistance wiring in the switch circuit
- Corroded, loose, or moisture-damaged switch connector
- Internal ECM failure in reading the input circuit
- Non-OEM fuel system modification affecting the expected signal
- Incorrect installation of alternative fuel components
02. Symptoms You Will Notice
- Check Engine Light illuminated
- Engine may run rough or have reduced performance when switching fuels
03. Step-by-Step Diagnosis
Scan for codes and verify P1168 is present
Inspect the fuel select switch and its connector for damage or corrosion
Test the switch circuit for continuity, shorts, and proper voltage
Check for any aftermarket fuel system modifications
If all else is normal, test the ECM or check for software updates
1. Frequently Asked Questions
Is it safe to drive?▼
Yes, but the vehicle may not properly adjust for the selected fuel, potentially causing reduced performance or drivability issues. It is recommended to have it diagnosed soon.
How much does it cost to fix?▼
Typically between $100 and $300, depending on the cause. A switch replacement is usually $50-$150 plus labor, while wiring repairs or ECM issues can be more.