P2404 code — how to fix error fast

As harmless as some OBD2 codes like P2404 may seem at first, they can all lead to huge complications and this code is a perfect example of this. As something that starts as a matter of gas emissions, it’s often pretty related to engine problems or even potential breakdowns.

So, let us guide you through the P2404 code meaning so we can tell you exactly what you need to do to diagnose and tackle the issue.

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What does the P2404 code mean?

The P2404 code indicates a problem with the EVAP system’s leak detection pump (LDP) control circuit. The LDP’s primary function is to detect leaks in the EVAP system by measuring pressure changes in the fuel tank and lines. If the LDP control circuit detects an issue, it will trigger the code.

The consequences of this code can include decreased fuel efficiency, increased emissions, and a rough idle. Other symptoms may include the check engine light illuminating, a gas smell, and difficulty starting the vehicle.

What causes the P2404 code?

Several potential causes can trigger the P2404 code, including a faulty LDP, a damaged EVAP canister, or a broken or disconnected hose. Other causes may include a damaged EVAP pressure sensor, a malfunctioning purge valve, or a faulty EVAP vent valve.

Faulty LDP

A faulty LDP is a common cause of the P2404 code. The LDP sensor can fail due to age, wear and tear, or damage. When this occurs, it can cause the LDP control circuit to detect a problem and trigger the code.

Damaged EVAP canister

The EVAP canister is responsible for storing fuel vapors until they can be burned in the engine. If the canister becomes damaged, it can cause a leak in the system, which can trigger the code.

Broken or disconnected hose

Hoses in the EVAP system can become damaged or disconnected over time, causing a leak. This leak can trigger the P2404 code.

Damaged EVAP pressure sensor

The EVAP pressure sensor measures the pressure in the fuel tank and lines to detect leaks. A damaged sensor can cause it to malfunction, leading to the code being active.

Malfunctioning purge valve

The purge valve is responsible for regulating the flow of fuel vapors from the EVAP canister to the engine. If the valve malfunctions, it can cause a leak, triggering the P2404 code.

Faulty EVAP vent valve

The EVAP vent valve regulates the flow of air into and out of the EVAP system. A malfunctioning valve can cause a leak, leading to the P2404 code.

Which car models does the P2404 code affect the most?

The P2404 code can occur in any vehicle with an EVAP system, but it may be more common in certain models. Some car models that are more likely to experience the code include:

• Jeep Wrangler: The Wrangler is one of the first cars that come to mind when it comes to this issue due to their complex EVAP systems and larger fuel tanks prone to leaks.
• Dodge RAM: The RAM also suffers from this code mostly due to the same reasons as the Wrangler.
• Chevy Silverado: As you might have guessed, the Chevy Silverado is yet another among car models that are prone to experiencing issues with this code.

How to diagnose the P2404 code

There are several steps involved in diagnosing the P2404 code. The first step is to use a diagnostic scanner to read the code and determine the cause of the problem. Next, you may need to perform several tests, depending on the suspected cause of the code.

Use an OBD2 scanner

To diagnose the P2404 code, you will need a diagnostic scanner and a multimeter to look for other related codes or check for related problems.

Check for fuel leaks

The next step is to look for fuel leaks that may indicate an issue with exhaust gasses and increased emissions that may have been caused by EVAP canister issues.

Inspecting the EVAP system and pressure sensor

There are several tests you may need to perform to diagnose the P2404 code, depending on the suspected cause. These tests may include a smoke test to detect leaks, a visual inspection of the EVAP system, and testing of the LDP sensor and EVAP pressure sensor for their functionality.

How to fix the P2404 code

Fixing the P2404 code will depend on the underlying cause. Some potential fixes include replacing a faulty LDP, repairing or replacing a damaged EVAP canister, or repairing or replacing a broken or disconnected hose.

Replace a faulty LDP

If a faulty LDP has been the reason for the issue in your car all along, you can replace it and solve the issue by removing the code. This fix can cost from $100 to $300 depending on your vehicle type and model.

Repair an EVAP canister

In case the charcoal canister for the EVAP system is causing trouble, you can repair it or even replace it to fix the code. This one is a bit more expensive to fix and it could range up to $500 in repair bills.

Seal any fuel leaks

If there are fuel leaks detected in your vehicle’s exhaust system or fuel lines, it’s important to fix them. You can use a smoke test that’s often performed by experienced mechanics to solve this issue by finding the leak easily.

How to prevent the P2404 code

Preventing the P2404 code is essential for maintaining your vehicle’s performance and preventing costly repairs. We have a few tips for you if you decide to take it seriously with the code’s prevention:

• Perform routine maintenance of the EVAP system
• Make sure there are no fuel leaks
• Perform proper fuel and emissions system inspections

Routine maintenance includes checking for damaged or disconnected hoses, replacing the EVAP canister when necessary, and inspecting the purge and vent valves for proper operation. A certified mechanic can perform these checks during your vehicle’s regular maintenance appointments.

Our take

Overall, the P2404 code can cause significant problems with your vehicle’s performance and lead to costly repairs if left untreated. Understanding the code’s meaning, potential causes, and diagnostic and repair procedures is critical for maintaining your vehicle’s health.

By following the preventative measures outlined in this article and seeking professional help when needed, you can keep your vehicle running smoothly and avoid the code.