Understanding P0021 Nissan Code: Symptoms, Causes, and Fixes

Every vehicle communicates its health through specific codes, and Nissan is no exception. You may encounter codes like the P1778 Nissan signifying problems with the step motor function, or the P1148 Nissan code that indicates issues with the closed-loop control function. However, another common error code that often puzzles Nissan owners is the P0021 code.

This guide aims to demystify the P0021 Nissan code, enabling you to understand its implications, diagnose the issue, and take appropriate actions to rectify it. We’ll delve into the meaning of this error, its common symptoms and causes, and provide a step-by-step guide to diagnosing and fixing this engine code issue.

Decoding the Language of Cars: The Importance of Diagnostic Codes

Before we dive into the specifics of the P0021 Nissan code, it’s important to understand what diagnostic codes are and why they matter. Cars, like any other machines, can experience issues and malfunctions. To communicate these problems, they use a system of diagnostic codes.

These codes are a language of their own, each one telling you a different story about what’s going on under your vehicle’s hood. Once you understand these codes, you can quickly diagnose and address issues, saving time and money on unnecessary repairs. In essence, these codes are your vehicle’s way of asking for help, with each one corresponding to a specific issue.

If that sounds confusing, don’t worry! In simpler terms, your car is telling you that something is interfering with its ability to time the opening and closing of the intake valves on one side of your engine. This can affect your vehicle’s performance, fuel economy, and even lifespan.

What is P0021 Nissan Code

P0021 Nissan code refers to an issue that affects your vehicle’s camshaft position. In technical terms, it’s an indication that the camshaft position is too advanced for Bank 2. This is part of Nissan’s On-Board Diagnostics II (OBD-II) system. The OBD-II system monitors and controls the performance of the engine, ensuring that it functions optimally.

So, when the P0021 code appears, it means that your engine’s camshaft position isn’t correct. This can affect your vehicle’s performance and may cause more severe engine problems if not addressed promptly.

Symptoms of P0021 Nissan Code

Knowing the common symptoms associated with the P0021 Nissan code can help you spot this issue early on, thereby avoiding more severe engine damage. These symptoms can include:

  • Decreased engine performance: You may notice that your Nissan isn’t performing as well as it usually does. The acceleration might feel sluggish or the fuel efficiency might decline.
  • Unusual engine noise: The P0021 Nissan code can often cause unusual noise from your engine. This might sound like rattling, pinging, or knocking – anything out of the ordinary.
  • Check engine light illuminated: Perhaps the most noticeable symptom is the check engine light on your dashboard. When you see this, it’s important to investigate further as it could be due to the P0021 Nissan code or another engine-related issue.

Common Causes of P0021 Nissan Code

There can be a few different reasons why your vehicle is displaying the P0021 Nissan code. Here are some of the most common causes:

  • Dirty or poor-quality oil: Your vehicle’s oil plays a crucial role in ensuring smooth engine performance. If the oil is dirty or of poor quality, it can affect the Variable Valve Timing (VVT) system and result in the P0021 code.
  • Faulty camshaft position sensor: The camshaft position sensor is essential for monitoring the speed at which the camshaft is rotating. If it’s faulty, it can trigger the P0021 code.
  • Misaligned timing chain/belt: The timing chain or belt helps synchronize the rotation of the crankshaft and the camshafts so that the engine’s valves open and close at the correct times. If this is out of alignment, it can result in the P0021 code.

How to Diagnose P0021 Nissan Code

Diagnosing the P0021 Nissan code can be a bit technical but with the right guidance, it’s entirely doable. Here’s a step-by-step process:

  1. Check the engine oil: Start by checking the oil level and its quality. If the oil is dirty or of a lower grade than your vehicle’s specifications, it may be causing the problem.
  2. Examine the timing chain/belt: The timing chain or belt should be in proper alignment. If it’s not, it could be the reason behind the P0021 code.
  3. Test the camshaft position sensor: Use an OBD-II scanner to test the camshaft position sensor for faults. If it’s not working correctly, it can trigger the P0021 code.

How to Fix P0021 Nissan Code

After you’ve diagnosed the P0021 Nissan code, the next step is to fix the issue. Here’s a simple guide to help you through this:

  1. Change the oil: If the engine oil is the issue, change it and replace it with the correct grade and quality as per your vehicle’s specifications.
  2. Adjust or replace the timing chain/belt: If the timing chain or belt is out of alignment, it may need to be adjusted or replaced. This is a complex job that’s best left to a professional mechanic.
  3. Replace the camshaft position sensor: If your OBD-II scanner identified a fault with the camshaft position sensor, it will need to be replaced.

How much does it cost to fix the P0021 Nissan code?

The cost to fix the P0021 Nissan code can vary significantly depending on the underlying cause of the issue. Here are a few possibilities:

  1. Engine Oil Change: If the cause is dirty or low-quality oil, the cost will be relatively low – roughly around $50 to $100 depending on the oil type and your location.
  2. Camshaft Position Sensor Replacement: Replacing a faulty camshaft position sensor can be a bit more expensive, with costs typically ranging from $150 to $300 including parts and labor.
  3. Timing Chain/Belt Replacement: If the timing chain or belt is the issue, the repair costs can be quite high. These repairs are labor-intensive and the parts themselves can be expensive. You may expect to pay anywhere from $500 to $1,000 or more.

Remember, these are just estimates and actual costs can vary based on labor rates in your area, the specific model of your Nissan, and the exact nature of the problem. It’s always best to get a few quotes from different mechanics to ensure you’re getting a fair price.


What can cause the P0021 Nissan code to appear?

Several factors can cause the P0021 Nissan code to appear, including dirty or poor-quality engine oil, a faulty camshaft position sensor, or a misaligned timing chain/belt.

Do I need to see a mechanic to fix the P0021 Nissan code?

While some of the steps to diagnose and fix the P0021 Nissan code can be done yourself, certain tasks, such as replacing the timing chain/belt or the camshaft position sensor, may require professional help, especially if you are not comfortable performing these tasks yourself.

Can I ignore the P0021 Nissan code?

Ignoring the P0021 Nissan code is not advised as it can lead to serious engine issues over time. It can cause your engine to run poorly, reduce fuel efficiency, or even lead to engine damage. If you notice this code, it’s best to address it promptly.

Can the P0021 Nissan code affect my vehicle’s fuel efficiency?

Yes, the P0021 code can potentially affect your vehicle’s fuel efficiency. This is because the camshaft’s position can influence the timing of fuel injection and ignition, both of which are vital for optimal fuel economy.

How does the camshaft position sensor work?

The camshaft position sensor gathers and sends information about the camshaft speed to the vehicle’s electronic control module. This data is used by the ECM to control ignition and fuel injection timing.

Can I drive my Nissan with the P0021 code?

While your vehicle may still be operational with the P0021 code, it’s generally not recommended to ignore this issue. The code suggests there could be a problem with your engine’s timing system, which can lead to serious damage if left unchecked. Always consult a mechanic if you’re unsure.

Is the P0021 Nissan code specific only to Nissan vehicles?

No, the P0021 code is a generic powertrain code that can appear in any vehicle, not just Nissans. It indicates a problem with the camshaft position, specifically that the “A” camshaft position in bank 2 is over-advanced. However, the implications and fixes can vary slightly depending on the make and model of the vehicle.


Understanding what the P0021 Nissan code means and knowing how to diagnose and address this issue is integral for Nissan owners. A vehicle is an investment, and taking care of it requires ongoing maintenance and attention to detail, particularly when it comes to engine performance. With this guide, you’re better equipped to address the P0021 Nissan code promptly and effectively. Remember, catching these issues early on can help prevent more significant engine problems down the line, protecting your investment and ensuring a smoother ride. However, if you’re ever unsure or uncomfortable diagnosing or fixing this issue, don’t hesitate to consult with a professional mechanic. Safe driving is always the best driving.