How To Fix P0330 OBD2 Error Code? Knock Sensor 2 Circuit

The P0330 OBD-II error code is defined as the Knock Sensor 2 Circuit Malfunction. This error is detected by the Engine Control Unit(ECU) when the knock sensor 2 in Bank 2 is not working properly. A Check Engine sign is illuminated and remains on until the error code is resolved.

What does it mean?

When the error code P0330 is set in the memory of the Engine Control Unit(ECU), it means that the knock sensors used in the vehicle sense an excessive amount of NOx gas that has been released in the engine.

This might be due to some unwanted proportion of air/fuel mixture in the engine. This may cause less power to be delivered to the engine.

Symptoms of P0303

The P0330 error code is not as highly dangerous as other error codes in the engine. At times, there might be no noticeable changes in the engine or the vehicle’s performance while driving. This can cause drivers to not be aware of any malfunction in the circuits of the engine. If this issue is left unresolved for long, more complications might follow. There are a couple of symptoms however that may be present during a P0330 code error in the engine and are listed below:

  • The Check Engine sign is turned on and it might remain on until the error has been resolved.
  • There also might be a loss of engine power in the vehicle while driving or accelerating.

What are the causes of p0303?

The P0330 code error mainly deals with the malfunctioning of the knock sensors. The knock sensor 2 in bank 2 is targeted to be where the error is detected by the Engine Control Unit. When the circuit of the sensor is not working properly, it sends an error input to the ECU. There are some root causes for this error code to occur in a vehicle. Some of them are:

  • The knock sensor 2 itself can be faulty and might be sending error inputs to the Engine Control Unit.
  • There might be a poor connection between the knock sensors and the harness used.
  • Open or short wire in the knock sensor wiring harness could be an issue.
  • The engine control unit itself could have failed due to poor programming or old condition.
  • The engine coolant system might not be functioning properly.
  • The engine might be running in an excessively lean condition.

How do you diagnose a P0330 error?

To diagnose a P0330 error code, a licensed professional mechanic might be needed. As there might be no visible issues with the P0330 error in a vehicle, the driver might not be knowledgeable to check and resolve the issue. 

A mechanic will first use an OBD-II scanner to check for the error codes that have been stored in the memory of the Engine Control Unit. If there is any other error code in the memory, those need to be addressed and resolved promptly. Then the mechanic will clear the code with the freeze frame data and take the vehicle for a test drive.

During the drive, the mechanic will try to duplicate the freeze frame data by driving under similar conditions. The live data will then be scanned to check the engine coolant temperature. If there are any cooling system problems, then that is needed to be dealt with to make sure the engine doesn’t overheat. Overheating issues in the engine can be a major problem and bring about several other complications and error codes in the vehicle.

Then, the mechanic will visually assess the engine parts associated with the error like the cooling system, knock sensors, wirings, and connections between the engine control unit and the sensor carefully. If nothing is amiss, then the engine control unit will be checked for any faults.

Common mistakes while diagnosing

There are some common mistakes one can make while diagnosing the P0330 error code. As this error mainly deals with the knock sensor 2 in bank 2, many drivers can be in a hurry to replace the sensor.

This however may not be the root cause of the problem in every scenario. Sometimes, the problem might lie with the engine coolant system or the fuel system. In these cases, replacing the knock sensor without thorough inspection might not work and end up wasting precious time and money.

Thus, ensuring the coolant system and the fuel system is in their best working condition is necessary.

How do you fix a P0330 error?

The P0330 error code in a vehicle is not determined to be an immediately dangerous situation while driving. As some vehicles do not show any symptoms of the error except lighting up the Check Engine sign, there is not much to worry about. The driver can easily drive the vehicle to a safe location and seek help from a professional to resolve the issue. The tools needed to fix this issue are easily available in a mechanic’s toolkit box. Some of the equipment used might involve screwdrivers, coolant, wirings, connectors, knock sensors, temperature guns, clamp meters, digital multimeters, etc.

To fix the knock sensor malfunction, there are a few steps that can be followed. However, repairing methods may vary from vehicle to vehicle. Some ways that could be used to fix the error are:

  • Fixing connection issues between the sensor and the engine control unit
  • Replacing worn-out connection wirings or harness
  • Cooling down the temperature of the engine using a coolant
  • If the engine control unit is found to be faulty, fixing its programming or replacing the unit
  • Replacing the knock sensor if found faulty

How can you avoid further errors?

To be able to observe and fix this error, an advanced level scan tool is required. It lets you observe the live data stream that can be used to assess and check the vehicle’s performance like resistance, operating voltage, and many others.

It is therefore difficult to pinpoint and be aware of this error in a vehicle. To ensure that the vehicle is running smoothly and the engine is in excellent working condition, it is best to let your vehicle receive the standard servicing and maintenance required frequently.