P0329 Knock Sensor 1 Circuit High Input (Bank 1 or Single Sensor)

As a car owner, it can be frustrating when you encounter problems with your vehicle. One of the most common issues that you might encounter is a fault with the Knock Sensor 1 Circuit High Input (Bank 1 or Single Sensor), also known as the code P0329. In this article, we will explore what the P0329 code means, what causes it, and how to fix it.

What is the P0329 Code?

The P0329 code is a generic OBD-II code that indicates a fault with the Knock Sensor 1 Circuit High Input (Bank 1 or Single Sensor). The Knock Sensor (KS) is a device that detects the knocking or pinging sound that occurs in the engine when fuel detonates in an uncontrolled manner. The KS sends a signal to the Engine Control Module (ECM) to adjust the engine’s timing to prevent the knocking sound.

When the KS detects a high input signal, it means that the engine is experiencing too much knock or pinging. This can cause damage to the engine if left unchecked, and the ECM will trigger the P0329 code to warn the driver that there is a problem.

What Causes the P0329 Code?

There are several possible causes of the P0329 code, including:

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  1. Faulty Knock Sensor – The KS may be faulty and sending a high input signal even when there is no knocking or pinging in the engine.
  2. Wiring Issues – The wiring that connects the KS to the ECM may be damaged or corroded, causing a high input signal.
  3. Engine Problems – The engine may be experiencing excessive knocking or pinging due to a variety of issues, including low-quality fuel, carbon buildup, or worn-out spark plugs.
  4. Faulty ECM – In rare cases, a faulty ECM may be sending a high input signal to the KS.

How to Fix the P0329 Code?

The first step in fixing the P0329 code is to diagnose the problem correctly. You can do this by using an OBD-II scanner to read the code and determine the underlying cause. Once you have identified the cause, you can take the following steps to fix the problem:

  1. Replace the Knock Sensor – If the KS is faulty, it will need to be replaced. This is a relatively simple procedure that involves removing the old sensor and installing a new one.
  2. Check the Wiring – If the wiring is damaged or corroded, it will need to be repaired or replaced. This can be a more complex procedure, and you may need to consult a mechanic.
  3. Address Engine Problems – If the engine is experiencing excessive knocking or pinging, you will need to address the underlying issue. This may involve using higher-quality fuel, performing a carbon cleaning, or replacing worn-out spark plugs.
  4. Replace the ECM – In rare cases, a faulty ECM may be causing the high input signal. If this is the case, you will need to replace the ECM. This is a complex procedure that should only be attempted by a qualified mechanic.


The P0329 code can be a frustrating problem for car owners, but it is usually a relatively easy fix. By correctly diagnosing the underlying cause of the code, you can take the appropriate steps to fix the problem and prevent any further damage to your engine. Remember, it is always better to address car problems as soon as possible to avoid more significant issues down the line.


  1. What are the symptoms of a faulty Knock Sensor?
    A: The symptoms of a faulty KS may include reduced engine performance, poor fuel economy, and illuminated Check Engine Light.
  2. Can I still drive my car with the P0329 code?
    A: It is not recommended to drive your car with the P0329 code as it can cause damage to the engine if left unchecked.
  3. How much does it cost to fix the P0329 code?
    A: The cost of fixing the P0329 code will depend on the underlying cause of the problem. A KS replacement can cost between $150 and $250, while more complex repairs can cost upwards of $500.
  4. How often should I replace my Knock Sensor?
    A: The KS does not usually need to be replaced unless it is faulty or damaged. However, it is recommended to have it inspected during routine maintenance to ensure it is functioning correctly.
  5. Can I fix the P0329 code myself?
    A: If you have the proper tools and knowledge, you may be able to fix the P0329 code yourself. However, it is always recommended to consult a qualified mechanic to ensure the problem is fixed correctly.