Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with the car's fuel shutoff valve. It's like a switch that controls the fuel flow, and it's not working right.
The P2666 code indicates that the vehicle's engine control module (ECM) has detected a low voltage or open circuit in the control circuit for the fuel shutoff valve B.
The fuel shutoff valve B is part of the fuel system that controls the flow of fuel to the engine. The ECM monitors the voltage and operation of this valve. If the voltage is lower than expected, it triggers the P2666 code. This could be due to a wiring issue, a faulty valve, or a problem with the ECM itself.
• Check Engine Light illuminated
• Engine stalling or not starting
• Poor fuel economy
• Faulty fuel shutoff valve B
• Open or shorted wiring in the control circuit
• Faulty ECM (Engine Control Module)
ECM: Engine Control Module
OBD-II: On-Board Diagnostics, second generation
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the fuel shutoff valve B for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the faulty fuel shutoff valve B.
• Reprogram or replace the ECM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Honda Accord
• Toyota Camry
• Ford F-150
• Regular maintenance checks
• Inspect wiring for wear and tear
• Ensure proper fuel system operation
Engine Performance
• Have the vehicle inspected by a professional if the Check Engine Light is on.
• Do not ignore the issue as it may lead to more severe engine problems.
Check with the vehicle manufacturer for specific warranty coverage on emissions-related components.
The P2666 code has been associated with fuel system issues and is not uncommon in vehicles with higher mileage.
Moderate – Should be addressed soon to prevent further engine issues.
Driving with a fuel system issue can lead to safety hazards and increased emissions.
• Engine running
• Fuel system pressurized
The fuel shutoff valve B is typically located near the fuel rail or fuel injectors.
Q: Can I drive my car with a P2666 code?
A: It's not recommended to drive for an extended period with this code, as it can lead to engine performance issues.
Q: How can I reset the P2666 code?
A: You can reset the code using an OBD-II scanner, but it's important to fix the underlying issue first.
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