Demystify the P0351 Error Code for Car Owners

1. What Does Error Code P0351 Mean?

Error code P0351 is a diagnostic trouble code related to the ignition system of a vehicle. Specifically, it indicates an issue with the ignition coil A primary/secondary circuit. The ignition coil is responsible for converting the low - voltage electrical current from the battery into the high - voltage needed to create a spark that ignites the air - fuel mixture in the engine's cylinders. When the Engine Control Module (ECM) detects a problem in the electrical circuit of ignition coil A, it sets the P0351 code.
 

2. What Are The Causes Of P0351?

• Faulty Ignition Coil: Over time, the ignition coil can wear out. High - voltage stress, heat, and vibration can cause internal damage to the coil's windings, leading to a loss of electrical insulation or an open circuit.
  
  
• Problematic Spark Plug: If the spark plug has a buildup of carbon deposits, oil, or other contaminants, it may not be able to produce a proper spark. This forces the ignition coil to work harder, increasing the likelihood of it failing and triggering the P0351 code.
  
  
• Wiring and Connector Issues: The electrical wires connecting the ignition coil to the ECM and the battery can develop problems. Broken wires, corroded connectors, or loose connections can disrupt the flow of electrical current. 
  

3. Which Brands of Vehicles Will Trigger The P0351 Code?

The P0351 code can be triggered in a wide variety of vehicle brands. It is not limited to any particular make or model. Both domestic and foreign vehicles, including popular brands like Ford, Chevrolet, Toyota, Honda, BMW, and Mercedes - Benz, may encounter this issue. 

4. Symptoms of Error Code P0351?

• Engine Misfires: One of the most common symptoms is engine misfires. When the ignition coil A fails to provide the necessary high - voltage spark, the air - fuel mixture in the corresponding cylinder will not ignite properly. This results in a rough - running engine, and you may feel vibrations or a shuddering sensation while driving.
  
  
• Reduced Engine Power: The engine's overall power output will be reduced. You may notice that the vehicle has difficulty accelerating, especially during overtaking or when climbing hills.
  
  
• Illuminated Check Engine Light: The check engine light on the vehicle's dashboard will illuminate. This serves as an early warning sign to the driver that there is an issue with the vehicle's engine or emission control system.
  
  
• Increased Fuel Consumption: An engine misfire caused by the P0351 code can lead to inefficient combustion. As a result, the engine will consume more fuel to produce the same amount of power. You may find that you need to refuel more frequently than usual.
  
  
  
  

5. How Serious is The P0351 Code?

The P0351 code is of moderate to high severity. While it may not immediately render the vehicle immobile, driving with this issue can cause significant problems. Continued operation with a misfiring cylinder can lead to unburned fuel entering the exhaust system, which can overheat and damage the catalytic converter. The catalytic converter is an expensive component to replace, and its failure can also lead to increased emissions, making the vehicle fail emissions tests. 

6. Can I Continue to Drive With The P0351 Code?

It is not advisable to continue driving with the P0351 code. Although the vehicle may still be operable, the risks associated with driving with a misfiring engine are significant.  If you must drive, keep your speed low and avoid high - load situations such as towing or driving on steep inclines. However, it is best to have the vehicle repaired as soon as possible.

7. How To Fix the P0351 Code?

• Replace the Ignition Coil: If the ignition coil is found to be faulty, it should be replaced with a new one. Make sure to choose a high - quality replacement coil that is compatible with your vehicle's make and model.
  
  
• Check and Replace Spark Plugs: Inspect the spark plugs for signs of wear, fouling, or damage. If they are in poor condition, replace them. Spark plugs should be replaced at the intervals recommended by the vehicle manufacturer, usually every 30,000 - 100,000 miles depending on the type of spark plug (copper, platinum, or iridium).
  
  
• Inspect and Repair Wiring and Connectors: Thoroughly check the electrical wires and connectors associated with the ignition coil. Repair any broken wires by soldering or using wire splicing kits. Clean any corroded connectors with a suitable electrical contact cleaner and ensure that all connections are tight.
  
  
  
  

8. Specific Steps for iCarsoft CR MAX to Solve The P0351 Code

• Connect the iCarsoft CR MAX: First, turn off the vehicle's engine. Locate the OBD - II (On - Board Diagnostics II) port, which is usually located under the dashboard on the driver's side. Connect the iCarsoft CR MAX to the OBD - II port.
  
  
• Power On the Device: Turn on the vehicle's ignition (but do not start the engine). The iCarsoft CR MAX Vehicle Diagnostic Tool will power up and establish communication with the vehicle's ECM.
  
  
• Select the Vehicle Make and Model: Use the device's menu to select the correct make and model of your vehicle.
  
  
• Read the Fault Codes: Navigate to the "Read DTCs" (Diagnostic Trouble Codes) option on the iCarsoft CR MAX. The tool will retrieve all the stored fault codes from the ECM, including the P0351 code.
  
  
• Clear the Codes: After repairing the problem, use the iCarsoft CR MAX to clear the P0351 code from the ECM's memory. This will turn off the check engine light if the issue has been resolved. 
  
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9. The Cost of Fixing the P0351 Code

The cost of fixing the P0351 code can vary. A new ignition coil can cost anywhere from  200, depending on the vehicle's make and model and the quality of the replacement part. Spark plugs typically cost between  50 for a set, and the cost of labor for replacing them is usually around  100. If the problem is with the wiring and connectors, the cost of repair will depend on the extent of the damage. 

10. Ways to Prevent the Occurrence of Error Code P0351

Regular Maintenance:

• Spark Plug Replacement: Follow the vehicle manufacturer's recommended schedule for spark plug replacement. Regularly replacing spark plugs helps maintain proper ignition performance and reduces the strain on the ignition coil.
  
  
• Ignition System Inspection:Periodically inspect the entire ignition system, including the ignition coils, wires, and connectors. Look for signs of wear, corrosion, or damage. This can be done during routine oil changes or at least once a year.
  

Use Quality Parts:

• Fuel and Lubricants: Use high - quality fuel and lubricants. Clean fuel helps prevent carbon deposits from forming on the spark plugs, while good - quality engine oil reduces wear on the engine components, which in turn helps the ignition system work properly.
  
  
• Replacement Parts:  When replacing any components in the ignition system, always choose high - quality replacement parts. Cheap, low - quality parts may not perform as well and can fail prematurely, leading to the P0351 code.

Avoid Harsh Driving Conditions:

• Overheating: Try to avoid driving in conditions that can cause the engine to overheat, as excessive heat can damage the ignition coil and other components.
  
  
• Vibration and Shock: Minimize driving on rough roads or engaging in activities that subject the vehicle to excessive vibration and shock. These can loosen electrical connections and cause damage to the ignition system components over time.
  
  
  
  

11. What Else Can iCarsoft CR MAX Do for Your Car?

The iCarsoft CR MAX is a versatile Vehicle Diagnostic Tool. In addition to helping diagnose and fix the P0351 code, it can read and clear diagnostic trouble codes from various other vehicle systems. This includes the transmission system, anti - lock braking system (ABS), airbag system, and more.

It can also perform live data streaming, allowing you to monitor real - time vehicle parameters such as engine RPM, coolant temperature, throttle position, and oxygen sensor readings. This data can be invaluable for diagnosing complex issues, performing maintenance, and ensuring the overall health and performance of your vehicle.

                                   Learn More about iCarsoft CR MAX