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When the check engine light illuminates your vehicle's dashboard, any car owner knows that this is a cause for concern. Error codes like P0324 on an OBD2 scanner mean that something is wrong with your automobile's engine and should be resolved as soon as you can.
We know these kinds of car error codes can make you paranoid and ask tons of questions in your head. Don't worry! This guide will help you figure out the symptoms, causes, and how to fix code P0324.
What does Code P0324 mean?
The P0324 is a trouble code for "Knock Control System Error" which can occur for different reasons. This should be diagnosed and fixed as soon as possible to avoid any more problems with your engine. So, how does this code come up?
When the knock control system sends an incorrect voltage reading to the Powertrain Control Module (PCM), it detects and records a P0324 error code and may cause the Check Engine Light to illuminate. So, what does the knock control system do?
The knock control system keeps track of the engine's cylinders and provides input signals to the PCM when anything goes wrong. The PCM uses a knock prediction algorithm to forecast when a knock will occur and modify fuel supply and ignition timing to the appropriate cylinder(s) to avoid knocks and misfires.
Symptoms of Code P0324
When the knock control system (KCS) is working properly, you will not notice anything wrong with your vehicle's performance. However, if your knock control system has a misfire or is testing poorly during an inspection, this could result in an engine misfire/knocking/pinging or running rough at idle or while driving.
Symptoms of these issues include:
- Engine hesitation under load
- Engine sputtering while idling/ clogged fuel injector (<600 RPMs)
- Poor throttle response time
Causes of Error Code P0324
Apart from the illuminated check engine light, various things can cause the code P0324 to appear. Here are the common causes of this trouble code:
- Knock Sensor Failure/Damage
- Open or Shorted Knock Sensor Wiring
- Intermittent open or short in Knock Sensor wiring
- Poor Electrical connection decrease automobile acceleration
- Incorrect Knock Sensor used during Crank Angle Sensor installation (after engine repair)
How to Fix Code P0324?
These are some methods that will assist you in resolving the OBD Code P0324:
- Indicate whether the engine is banging, pinging, or misfiring.
- Fix a faulty electrical connection in the knock sensor circuit.
- Replace the knock sensor's electrical harness.
- The PCM should be replaced or reprogrammed (uncommon)
If all other options fail, replace the knock sensor if necessary. This repair may necessitate the use of professional skills, so if you lack sufficient automobile repair knowledge, you can take your car to a professional mechanic. However, if you are confident in your ability to repair it yourself, you can follow the steps below.
Step-by-step Guide to Replacing the Knock Sensor
These methods may vary depending on the make and model of your vehicle.
- The first thing you need to do is disconnect the negative battery first. Next, remove both ends of intake hoses and the throttle control cable, and the throttle body control cable.
- After that, remove the throttle cable and the harness bracket from the intake manifold. This part is followed by disconnecting the EVAP (Evaporative Emission Control System) solenoid sub-harness, mass airflow sensor, and Knock sensor.
- Remove the throttle body and vent. Put these in a safe place.
- Remove the fuel lines. These fuel lines are located at the rear of the intake manifold on the driver's side.
- Remove the injector and engine wire harness. You will see the alternator connecter connected to the engine wire harness; disconnect it.
- Disconnect the throttle position sensor from its connector.
- Remove all manifold screws in reverse order, then remove the manifold to reveal the Knock sensors beneath the black plugs connected to a wiring harness.
- The Knock sensors must be removed by unscrewing and removing the connectors. After installing the new sensors, apply RTV (room temperature vulcanizing) adhesive to the plugs to prevent water leakage and tighten to 15 ft-lbs.
- Before fitting the new intake manifold gaskets, ensure all surfaces are clean. Reconnect all gasoline lines, brackets, EVAP line, intake hose, and other components. Also, reconnect the battery.
- Connect the black wire to the vehicle's negative terminal after you've finished this step and test to determine if the engine knock is still present. At this stage, if the engine knock is no longer present, you're set to go.
If none of those methods worked, it might be time to replace the PCM. You can take your vehicle to a reputable mechanic or repair it yourself. However, keep in mind that replacing the PCM yourself needs professional knowledge as it may worsen the problem if the procedure is not followed correctly.
If you are confident enough to do it yourself, we will try our best to help you. Here is the step-by-step guide you may follow, and we hope it walks you through the proper replacement of your PCM.
Step-by-step Guide to Replacing the PCM
The method of PCM replacement may differ depending on the vehicle's model and make. We chose the PT Cruiser as an example in this guide, hoping that it will give you an idea of how the replacement works.
What You’ll Need:
- Set of sockets
- Pre-programmed PCM
For the Removal:
- Make sure to remove the key from the ignition.
- Open the hood of your car and ensure to support it with the hood prop.
- Loosen the intake air hose clam and the air cleaner housing with a flat screwdriver.
- Detach the hose from the housing outlet.
- Slightly lift the air cleaner and remove the air inlet duct from the housing.
- Take out the engine compartment.
- With a ratchet and socket, loosen the negative battery cable terminal.
- Disconnect the terminal from the battery.
- Locate the PCM.
- Once, found disconnect it from the vehicle wiring harness.
- Pull the PCM bracket off the firewall by removing the three PCM bracket retaining nuts.
- Remove the old PCM and set it aside.
For the Installation:
- Place the new PCM on the bracket and ensure it is in the proper position.
- Using the wrench and socket, install the retainer nuts.
- Place the PCM assembly on top of the firewall. Install the retention bolts and twist them to 35 inch-pounds. Connect the electrical connectors and make sure the lock tabs are firmly in place.
- The negative cable termination should be connected to the negative battery post. Torque the terminal pinch bolt to 110 inch-pounds.
- Place the air cleaner housing in its proper location. Install the fresh air inlet duct in its housing port, then fit the intake air hose over the housing's outlet port. Tighten the clamp on the intake air hose firmly.
Vehicle Parts that You May Need to Repair or Replace
Aside from the knock sensor itself, there are a few components you should inspect and fix if necessary. This ensures that you don't make any errors when troubleshooting the code P0324. Some parts and components that may need to be repaired or replaced are listed below.
A faulty knock sensor may prevent the engine from accelerating when traveling on the highway, resulting in a loss of fuel mileage. If this occurs, you should have a trained mechanic examine the vehicle to determine why it is difficult to accelerate.
Knock Sensor's Circuit
If one or more engine cylinders "knock," the Knock Sensor circuit signals the engine computer. This "knocking" is caused by an explosion of the air-fuel combination, resulting in decreased power and the potential for engine damage. Otherwise, replace the knock sensor if any wires leading to it are damaged or frayed.
Knock Sensor Harness
The heat from the engine might cause a malfunctioning knock sensor wire harness to fail. If the wire harness is in terrible shape or challenging to reach the harness and sensors, have a mechanic install new sensors when replacing the saddle to save future headaches.
Knock Control System
Using an OBD-II scanner, the mechanic will first check the system for any stored codes. Then they'll examine for any issues with the wiring, connections, harness, or the rest of the knock control system with a visual inspection. They'll then use an oscilloscope or a knock sensor tester to see if the knock sensor is faulty or if there's something else wrong.
Powertrain Control Module
A corrupted PCM may become irregular to the point that your car may have trouble starting or stall while running. When the vehicle is running, you'll see that the exhaust fumes have shorted, and the emissions system control signals will begin to fail, so if the PCM isn't operating correctly, it has to be replaced right away.
If your check engine light continues to light on, then we think it's time for you to call for a professional mechanic's help.
P0324 Code FAQs
1. What are some symptoms that may cause this code to trigger in my car?
When the code P0324 triggers, you may notice rough idling, engine pinging during acceleration and deceleration, engine stalling under load, or other misfire symptoms.
2. What causes the knock control system to go out?
A failed knock sensor can cause this irregular knocking detected by the PCM when receiving data from the sensors connected to the knock control system. When this happens, fix your knock sensor problem before moving on to other possible fixes for a P0324 code.
Many automotive technicians and mechanics will use the term "knock," but they actually mean pinging when gas ignites too early. Because of this confusion, people also refer to P0324 as an engine knock or ping code.
3. Can I drive having this error code on my dashboard?
You can still drive the car, though you'll probably experience some of the symptoms mentioned above. What you can't do is leave it unaddressed for very long because the engine will eventually malfunction and possibly even break with this problem left unattended.
4. How much is the cost of diagnosing code P0324?
If a mechanic diagnoses the problem, expect to pay about $100.00 for misfires and pings. However, the cost may vary depending on the make and model of the car. For example, for Ford the estimated cost is around $115, while BMW will cost around $130.
5. Do I need to address code P0324 asap?
Yes, you should get your car diagnosed and fixed as soon as possible. If you get stranded on the highway or in some other location where it would be unsafe to leave your vehicle, call for assistance immediately.