Error Code P2340: What It Means & What To Do?

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What does P2340 error code mean? The rough running of the engine is known as cylinder 5 above knock threshold. The cylinder will run lean if the fuel injector does not permit enough fuel into the cylinder which creates an engine knock. There is a calibration number in the side of the injectors which has to be entered into the PCM when it is changed. The P2340 error will be stored if the number is not entered into the PCM.

The engine knocking is sensed by the knock sensor which is also known as detonation or pinging with the help of piezoelectric element. The sensor is fixed to the cylinder block, cylinder head or either the intake manifold. A knock vibration from the cylinder block is detected as vibrational pressure. The pressure is changed into a voltage signal and forwarded to the ECM. The signal is used by the ECM to check the ignition timing and to safeguard the engine from this harmful pre-ignition.

What causes this problem with the Cylinder 5 Above Knock Threshold?

• The ECM might be defective.
• Damaged knock sensor.
• There might be an opening or the knock sensor harness might have a short circuit.
• The electrical connection of the knock sensor circuit might be weak.

1. Knock Sensor - Does your engine face starting trouble issues? Then the knock sensor can be faulty. Get the replacement for a faulty knock sensor from PartsAvatar.
2. Cylinder Head Gasket - If the cylinder head gasket is leaky, then you will see white smokes from the exhaust pipe which is an indication that the cylinder head gasket has to be changed quickly.
3. Sensor Connector - A faulty or damaged sensor connector will make the P2340 error code to get stored in your vehicle. Get rid of this error code by replacing the damaged sensor connector.
4. Intake Manifold - A decrease in power and acceleration indicates a broken intake manifold. Avoid the P2340 error by fixing it immediately.
5. Engine Control Module - Does your engine turn off without any reason? Then it’s a high time to replace your ECM as it can be faulty.
6. Fuel Injector - If the fuel injector is broken, then the gas will start leaking and can cause malfunctioning of the vehicle. Get rid of the P2340 error by replacing the damaged fuel injector.
7. Spark Plug - If the spark plugs are damaged, then you will experience trouble in starting the engine. Replace the defective spark plugs quickly.
8. Powertrain Control Module - If the sensor circuit is shorted it will overload the engine and damage the PCM module. If you find the powertrain control module to be damaged get the replacement from Parts Avatar.

We at Parts Avatar Canada care for our customers, and that’s why we will help you to diagnose P2340 code by listing out some major symptoms. They are mentioned below as follows:

Common Symptoms

• There might be a power loss and the vehicle while refuse to start as you accelerate along with the illumination of the service engine soon lamp and knocking off the spark.
• The soon lamp of the service engine will stay the same or it will keep flashing and go off erratically or stay on for a prolonged time and then shuts off for a small or lengthier duration.

Learn the ways with which you can correct this trouble code:

• Replacing the damaged fuel injector.
• Changing the defective spark plugs.

However, if you face any issue then we have stocked a wide range of best-priced PCM, ECM, spark plug, intake manifold, fuel injector, knock sensor, cylinder head, sensor connection and more to help you out in fixing your car.

It is essential to diagnose this fault code. Here are some steps which a mechanic should follow for diagnosing the problem that triggered a P2340 code to be stored:

• Either a knock sensor or multiple knock sensor which threads into the engine block is used by manufacturers.
• At least 2 knock sensors are needed by V-shaped engine blocks- a cylinder for each bank.
• Other manufacturers will prepare their vehicle with knock sensors for a single cylinder.
• The engine bank which has the cylinder 1 is referred to as bank1 and cylinder 1 is not available for bank 2.
• The knock sensor is a single wire sensor which uses the low voltage signal to identify more noise from the engine.
• If more noise is found in the internal engine, the knock sensor will be stuck where the circuit gets completed and a 5V input voltage signal is sent to the PCM.
• The voltage of the knock sensor is carefully looked after by the PCM and it responds accordingly.
• If the PCM identifies an irregular signal from the knock sensor, the engine timing will be adjusted so as to reduce the noise and further damage to the engine.
• Diagnose the code with the help of a scanner and DVOM.
• A manufacturer’s service manual will be essential.
• Carefully check the wires and connectors.
• The damaged wires, connectors, and other components have to be separated and repaired.
• After each successful diagnosis, recheck the system. Attach a scanner to the vehicle if every component is in proper working conditions and then retrieve both the stored codes and freeze frame data.
• This is highly helpful to find if there are any irregular conditions which made this error code to get stored in the vehicle.
• Clear all codes and retest the vehicle to see if any error has occurred.
• This will help you to know if the condition was irregular. Clear all codes and retest the vehicle to see if an error appears again.
• The condition will be erratic if the code does not show up instantly.
• In one such situation, you have to worsen the condition of the vehicle before proceeding for further diagnosis as this is a challenging task.
• The engine must have clean oil.
• Carry out the diagnostic procedure by listening for more engine noise.
• If you find any other DTC in the PCM, repair and fix them before fixing other error codes.
• Perform a manual oil pressure test, if you hear abnormal engine noise and relate your findings with the manufacturer’s recommendation.
• The damaged engine components must be replaced.
• Clear the error codes and the vehicle must be test driven to see if the repair was successful.
• If the engine works normally, separate the electrical connector from the sensor which was affected and sensor resistance must be checked.
• Link your findings with the specification of the manufacturer.
• Change the sensor if required.
• Clear the error codes and the vehicle must be test driven to see if the repair was successful.
•  Separate the connector from knock sensor and test the reference voltage id the sensor works well.
• If there is no reference voltage check for burnt or shorted wires to the knock sensor.
• The leaky engine oil into the wires and connectors of the knock sensor can cause a failure than that of the clean and dry wires and connectors.
• Separate the connectors from the knock sensor as well as its related controlled if the system works properly.
• Check for resistance and continuity on all the affected circuits.
• Relate your findings with the manufacturer’s recommendation and fix the circuits/ connectors which do not fulfill.
• Clear the error codes and the vehicle must be test driven to see if the repair was successful.
• Few of the sensors are placed on the areas of the engine which makes them unaffordable for testing.
• These vehicles which are well-placed with such knock sensor have to be checked through a process of elimination which shows that the failure was caused due to the knock sensor.
• While changing the knock sensor, ensure that it is not stuck into the coolant passage of the block engine.
• If the knock sensor is removed from the coolant passage of the hot engine, it can cause burns in the technician’s skin.

Common Mistakes When Diagnosing The P2340 Code

• Entering the fuel injector calibration into the PCM.
• Faulty fuel injector.
• Defective PCM.
• An issue with the wires.