Fuel Shutoff Valve Control Circuit Low
The P2666 code indicates that the Powertrain Control Module (PCM) has detected a low voltage condition in the control circuit of the fuel shutoff valve. This valve is responsible for cutting off fuel flow to the engine in certain conditions, such as during a collision or when the ignition is off. A low voltage signal suggests a short to ground, open circuit, or a faulty valve, which can prevent proper fuel shutoff and affect engine operation.
01. Most Common Causes
- Faulty fuel shutoff valve
- Short to ground in the control circuit
- Open circuit in the wiring or connector
- Failed PCM (rare)
02. Symptoms You Will Notice
- Check Engine Light illuminated
- Engine may not start or stalls unexpectedly
- Fuel odor or visible fuel leak
- Reduced engine performance
03. Step-by-Step Diagnosis
Step 1: Use a scan tool to confirm P2666 and check for other related codes.
Step 2: Visually inspect the fuel shutoff valve and its wiring for damage, corrosion, or loose connections.
Step 3: Test the valve's resistance with a multimeter; compare to manufacturer specs.
Step 4: Check for voltage at the valve connector with the ignition on; if low, trace circuit for shorts or opens.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
No, it is not safe. The fuel shutoff valve may fail to operate correctly, potentially causing fuel leaks or engine stalling, which can lead to accidents or fire.
How much does it cost to fix?▼
The cost typically ranges from $50 to $150 for parts and labor, depending on the cause. Replacing the valve is usually under $100, while wiring repairs may be less.