Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's computer has detected a leak in the system that carries fuel under low pressure. It's like having a small hole in a straw where fuel is supposed to flow smoothly.
The P240D code indicates that there is a leak in the low-pressure section of the alternative fuel system, which could affect the vehicle's fuel efficiency and performance.
The P240D code is triggered when the Engine Control Module (ECM) detects a leak in the low-pressure side of the alternative fuel system. This could be due to a damaged fuel line, a faulty pressure sensor, or a compromised fuel tank seal.
• Check Engine Light is on
• Reduced fuel efficiency
• Fuel odor near the vehicle
• Damaged or cracked fuel lines
• Faulty pressure sensor
• Loose or damaged fuel tank cap or seal
ECM: Engine Control Module, the computer that controls engine functions.
Alternative Fuel: Fuel other than traditional gasoline or diesel, such as CNG or LPG.
• Inspect fuel lines for visible damage or leaks.
• Check the fuel tank cap and seals for tightness and damage.
• Use a diagnostic tool to confirm the code and check pressure sensor readings.
• Replace damaged or cracked fuel lines.
• Repair or replace the faulty pressure sensor.
• Ensure the fuel tank cap is properly sealed or replace if damaged.
• OBD-II scanner
• Fuel pressure gauge
• Wrench set
$100 - $500
Moderate
• Toyota Prius
• Honda Civic CNG
• Chevrolet Volt
• Regularly inspect fuel system components.
• Replace fuel tank cap if it shows signs of wear.
• Use high-quality fuel to prevent system degradation.
Fuel System Leak
• Avoid driving with a leaking fuel system to prevent further damage.
• Regularly check for fuel odors around the vehicle.
Check your vehicle's warranty; fuel system components may be covered under emissions warranty.
This code has become more common with the rise of alternative fuel vehicles, as their systems can be more sensitive to pressure changes.
Moderate – Address the issue soon to avoid potential fuel system damage and reduced performance.
Driving with a fuel system leak can be hazardous and may violate emissions regulations.
• Vehicle at operating temperature
• System pressurized
The low-pressure fuel system components are typically located near the fuel tank and along the fuel lines leading to the engine.
Q: Can I drive my car with a P240D code?
A: It's not recommended to drive with a fuel system leak as it can be dangerous and affect vehicle performance.
Q: How can I fix a P240D code?
A: Inspect and repair any damaged fuel lines, replace faulty sensors, and ensure the fuel tank cap is secure.
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