P1404: EGR Closed Position Performance Issues Fix Guide

When your Chevy Tahoe suddenly turns on the check engine light with the P1404 code, it’s likely that the EGR valve is stuck due to carbon deposits - don’t worry, 90% of these can be fixed on your own! In this guide, we’ll explain what the P1404 code means, its symptoms, common causes, and step-by-step repair solutions.

What Does the P1404 Code Mean?

The P1404 OBD-II diagnostic trouble code stands for "EGR closed position performance problem." It is also referred to as a B-circuit fault in some systems. This code is triggered when the vehicle's powertrain control module (PCM) detects that the EGR valve is not closing properly.

Is the P1404 Code Important?

Yes. The EGR valve is responsible for recirculating a portion of the exhaust gas back into the engine intake to lower combustion temperatures and reduce harmful nitrogen oxide (NOx) emissions. If the EGR valve fails to close properly, it may cause:

• Inefficient engine;
• Increased emissions;
• Potential damage to other engine components.

Common Symptoms of the P1404 Fault Code

If your vehicle displays the P1404 fault code, look out for the following signs:

• Engine malfunction light (primary indicator light);
• Rough idle or slow acceleration;
• Black smoke coming from the exhaust;
• Failed emissions test;
• Engine knocking or unusual noises when accelerating;
• Decreased fuel efficiency.

These problems can worsen if left unchecked, so it's critical to take immediate action.

What Causes the P1404 Code?

The P1404 fault code is usually caused by one or more of the following:

• Faulty EGR valve (stuck, clogged, or damaged);
• Carbon deposits in the EGR system (most common cause);
• Damaged wiring or connectors in the EGR circuit
• Faulty EGR position sensor (incorrect valve position reading);
• PCM/ECU software malfunction (rare but possible).

How to Diagnose the P1404 Code

Step 1: Scan with an OBD-II Scanner: confirms the P1404 code and checks for other related codes.

Step 2: Inspect the EGR valve: check for carbon deposits or mechanical failures.

Step 3: Test the EGR passages: make sure they are not blocked.

Step 4: Inspect the wiring and connectors: check for corrosion, breaks or loose connections.

Step 5: Test the EGR position sensor: confirm it is sending an accurate signal.

Step 6: Check for PCM updates: some vehicles require a software refresh.

How to Fix a P1404 Fault Code

✅ Fix 1: Clean or Replace EGR Valve

Remove the EGR valve and clean out any carbon deposits. Replace if damaged.

✅ Fix 2: Clean EGR Passages

Use a wire brush or carburetor cleaner to remove stubborn carbon deposits from the intake manifold passages.

✅ Fix 3: Repair Electrical Connections

Repair or replace any damaged wires or connectors in the EGR circuit.

✅ Fix 4: Replace the EGR Position Sensor

If the sensor is reading incorrectly, it may need to be replaced.

✅ Fix 5: Update ECU Software

Some vehicles, especially Jeep and Dodge models, may require a software update.

🔧 Advanced solution: EGR Delete

In situations where there are no restrictions on emission regulations, some car owners will choose to completely delete the EGR system in order to pursue higher performance and fewer failures. This can also reduce a lot of maintenance costs. But please note that this method is illegal in many places. It is recommended to consider carefully before doing it.

Check for our recommended kits here: EGR Delete Kits.

Vehicle-Specific Fixes for P1404 Fault Codes

FAQs about the P1404 Code

1. Is P1404 serious?

The severity ranges from moderate to severe. If there are no other symptoms besides the check engine light, you can drive temporarily, but it should be repaired as soon as possible. If you notice smoke, knocking, or stalling, stop driving immediately and have it repaired.

2. Does a P1404 error affect fuel economy?

Yes. A faulty EGR valve can cause incomplete combustion and a rich fuel mixture, which can reduce your MPG (miles per gallon).

3. Can a P1404 clear itself?

It will only occur if the problem is intermittent (such as a loose connector). Otherwise, the problem will persist until it is repaired.

4. P1404 vs. P0404 – What is the difference?

P0404 is mostly “valve stuck open”, P1404 is “abnormal closed position”.

5. How much does it cost to fix a P1404 code?

Simple fixes like cleaning the EGR passages may only cost a few dozen dollars, while a full replacement can run into the hundreds. .

6. Can bad gasoline cause the P1404 code?

Indirectly, yes. Bad fuel can cause carbon deposits, which can clog the EGR system.

7. Why does the P1404 code keep coming back?

• Incomplete cleaning;
• Poor quality replacement parts;
• Wiring or sensor faults not addressed;
• ECU software not updated.

Pro Tip: Make sure all possible causes are addressed thoroughly, not just the visible ones.

Final Thoughts

The P1404 fault code is a common problem on Chevrolet, Jeep, Dodge, and Chrysler vehicles, and is usually caused by a clogged or faulty EGR valve. While you can clean or replace the EGR valve yourself, persistent problems may require professional diagnosis.

Key Takeaways:

✔ Never ignore a P1404 fault - it can reduce engine performance and emissions.

✔ Cleaning the carbon deposits is the most effective first step.

✔ If the problem persists, check the wiring and sensors.

✔ If DIY repairs don't work, seek professional help.

If all else fails, some owners opt to use an EGR delete kit, but this may be illegal in areas with strict emissions regulations - consult a professional before choosing this method.