P0094 OBD-II Trouble Code: Fuel System Leak - Small Leak Detected

P0094 code definition

Fuel System Leak - Small Leak Detected

What the P0094 code means

The P0094 code is set in a vehicle’s Powertrain Control Module (PCM) when it detects a small leak in the fuel system. It is most common on vehicles with diesel engines.

What are the causes of the P0094 code?

• Small leak in the injection pump
• Small leak in the injectors
• Small leak in the fuel lines and hoses
• Small leak in the fuel rail
• Small leak in the fuel filter
• Small leak in the fuel tank
• Fuel pressure decreased by the fuel pump, injector pump, a restriction in the fuel system, or a fuel pressure regulator

What are the symptoms of the P0094 code?

• Running out of fuel faster than normal
• Decreased fuel economy
• Check Engine Light illumination
• Fuel odors
• Risk of fire

How does a mechanic diagnose the P0094 code?

• Inspects the fuel system for leaks

• Repairs any leaks found

If no leaks are found in the fuel system:

• Conducts a fuel pressure test

If fuel pressure is lower than manufacturer-specified pressure:

• Inspects the fuel pump
• Inspects the injector pump
• Inspects the fuel pressure regulator

Common mistakes when diagnosing the P0094 code

Checking for leaks and, after not finding any leaks, replacing the fuel pressure regulator. This part is a common cause of this issue, however is is always best to know for sure that a part is faulty by testing it before replacing anything.

How serious is the P0094 code?

The P0094 code is not as serious as a P0093 code, due to the fact that the leak is smaller. However, considering that a fuel leak is still possible, the risk of a fire is also possible, which can become a very serious safety issue and could cause injury to the driver and passengers.

What repairs can fix the P0094 code?

• Replacing the fuel tank
• Replacing the fuel pump
• Replacing the fuel filter
• Replacing the fuel injectors
• Replacing the fuel injector pump
• Replacing the fuel pressure regulator
• Replacing a fuel hose or fuel line
• Replacing a fuel pressure sensor
• Repairing or replacing wiring that is associated with the fuel pressure sensor

Additional comments regarding the P0094 code

Just because this code says that a “small leak” has been detected in the fuel system does not mean that a leak actually exists. This code is set when the PCM sees a noticeable loss in fuel pressure. If the fuel pressure sensor or its circuitry are damaged, or the fuel pressure regulator, fuel pump, or fuel filter are faulty, this can cause a decrease in fuel pressure and therefore cause a P0094 code.

Need help with a P0094 code?

YourMechanic offers certified mobile mechanics who will come to your home or office to diagnose and repair your vehicle. Get a quote and book an appointment online or speak to a service advisor at 1-800-701-6230 to have this issue resolved.