Connect with us

Error codes

P0351 Code: symptoms & causes



Introduction to the P0351 code

The P0351 code is a diagnostic trouble code (DTC) that indicates an issue with the ignition coil A primary/secondary circuit. It typically appears on vehicles with gasoline engines and can be triggered by a variety of issues related to the ignition system.

When this code is set, it means that there is a problem with the electrical circuit between the engine control module (ECM) and one or more of the ignition coils. The ECM uses this circuit to control when each spark plug fires, so any disruption in this process can result in poor engine performance and potential damage.

There are several possible causes for a P0351 code, including faulty wiring or connections within the ignition coil circuit, damaged or malfunctioning ignition coils themselves, problems with other components in the engine management system such as sensors or actuators, and even issues with software programming within the ECM.

If left untreated, a P0351 code can lead to various symptoms such as rough idling or stalling at low speeds, decreased fuel efficiency due to incomplete combustion cycles caused by misfiring cylinders, and increased emissions levels that could cause your vehicle to fail state inspections.

Fortunately, diagnosing and resolving a P0351 fault is usually straightforward for experienced mechanics who have access to specialized diagnostic tools. These professionals will typically perform tests on all relevant components of your vehicle’s ignition system using multimeters and other equipment designed specifically for identifying faults in these types of circuits.

Overall though it may seem daunting at first glance; don’t worry too much about encountering this error – modern cars have become quite reliable over time thanks largely due diligence put into their design & engineering!

What causes the P0351 code to appear?

The P0351 code is a diagnostic trouble code that indicates an issue with the ignition coil A primary/secondary circuit. This means that there is a problem with the electrical connection between the ignition coil and its associated components, such as spark plugs or wires.

There are several possible reasons why this code might appear. One common cause is a faulty ignition coil itself. Over time, these coils can fail due to wear and tear or overheating, which can lead to short circuits or other electrical problems.

Other potential causes of the P0351 code include issues with wiring or connectors in the ignition system, as well as problems with other related components like spark plugs or fuel injectors. In some cases, issues with engine timing may also be responsible for triggering this error code.

To diagnose and fix the problem behind a P0351 error message, it’s important to have your vehicle inspected by a qualified mechanic who can perform tests on your car’s electrical system and identify any underlying issues. Depending on what’s causing this issue, you may need to replace parts like your ignition coil or repair damaged wiring in order to resolve it.

Ignoring a P0351 error could lead to further damage down the line, so it’s essential to address this issue promptly if you encounter it while driving your vehicle. With proper diagnosis and repairs from an experienced technician, however, you should be able to get back on the road safely and without any further trouble!

Symptoms of a P0351 code

The P0351 code is an OBD-II generic powertrain code that indicates a problem with the ignition coil A primary or secondary circuit. When this error code is detected, the vehicle’s Engine Control Module (ECM) will trigger the Check Engine light on the dashboard.

Here are some common symptoms of a P0351 code:

Engine misfire and hesitation:

When there is a problem with the ignition coil circuit, it can cause one or more cylinders to misfire. This can lead to poor acceleration, rough idling, and even stalling while driving.

Poor fuel economy:

A faulty ignition coil can also affect your car’s fuel efficiency. If your engine isn’t firing correctly due to a bad coil, it may burn more fuel than necessary to compensate for lost power.

Difficulty starting:

If you’re having trouble starting your car or notice that it takes longer than usual to start up, this could be another sign of an issue with the ignition system. Ignition coils play an important role in providing spark to ignite fuel in your engine; if they aren’t functioning properly, starting your car may become difficult.

Inconsistent performance:

Another symptom of a P0351 code is inconsistent engine performance. You may notice that at times your vehicle runs smoothly while other times it hesitates or runs roughly. This inconsistency could be caused by failing components within the ignition system such as spark plugs or wires in addition to problems with the coils themselves.

If you experience any of these issues while driving and suspect that you have a P0351 error code present in your vehicle’s computer system – don’t hesitate! Contacting an experienced mechanic for proper diagnosis and repair is crucial for restoring optimal performance and preventing further damage from occurring over time.

Diagnosing a P0351 code

If you have received a P0351 code, it means that there is an issue with one of your ignition coils. The first step in diagnosing this problem is to check the wiring and connections leading to the coil. Make sure all connections are secure, and inspect for any damage or corrosion.

Next, use a multimeter to test the resistance of the coil. A healthy ignition coil should have between 0.4 and 2 ohms of resistance. If your reading falls outside of this range, it may be time to replace the faulty component.

It’s also important to check for any other related codes that may be present alongside P0351. This can help identify any underlying issues that may be contributing to the problem.

If you’ve ruled out wiring issues and faulty coils as possible culprits, it’s worth checking your spark plugs next. Worn or damaged spark plugs can cause misfires which trigger P0351 codes.

Finally, if none of these steps have resolved your issue, it’s recommended that you bring your vehicle into a trusted mechanic for further diagnosis. They will be able to run more comprehensive tests on your vehicle’s electrical system to pinpoint exactly what is causing the problem.

In summary, diagnosing a P0351 code involves checking wiring and connections leading up to the ignition coil, testing its resistance with a multimeter, checking for other related codes present alongside P0351 , inspecting spark plugs for wear or damage before seeking professional assistance if none of these steps resolves the issue at hand

Repairing a P0351 code

If you have received a P0351 code, there are several steps you can take to repair the issue. Here are some of the most common solutions:

1. Check for loose connections or damaged wiring

The first step is to check all connections and wiring related to the ignition coil circuit. This includes inspecting the spark plug wires, coil pack connectors, and any other electrical components in the circuit for signs of damage or wear.

2. Replace faulty ignition coil(s)

If your inspection reveals that one or more ignition coils are not functioning properly, it may be necessary to replace them with new ones. It’s important to note that if one coil has failed, others may also be on their way out and should be replaced as well.

3. Test crankshaft position sensor

In some cases, a faulty crankshaft position sensor can cause a P0351 code to appear. To test this component, you will need an ohmmeter and access to your vehicle’s service manual for specific testing procedures.

4. Check PCM/ECM software updates

Sometimes manufacturers release software updates that address known issues like P0351 codes. Checking for available updates through your dealership or mechanic can help ensure that your vehicle is operating at its best.

5. Have a professional diagnose the problem

If none of these solutions work, it may be time to seek out professional assistance from an experienced technician who has access to specialized diagnostic equipment capable of pinpointing exactly what’s causing your engine trouble.

No matter which solution ends up being right for you and your vehicle, taking action sooner rather than later is always recommended when dealing with engine trouble. Ignoring a P0351 code can lead to more serious problems down the road, so it’s best to address any issues as soon as possible.

Preventing future P0351 codes

To prevent future occurrences of the P0351 code, it is important to properly maintain and care for your vehicle’s ignition system. Here are some steps you can take:

Regular maintenance

Make sure to follow the manufacturer’s recommended maintenance schedule for your vehicle. This includes regular tune-ups, oil changes, and air filter replacements. Keeping your engine in good condition can help prevent issues with the ignition system.

Check spark plugs and wires

Spark plugs and wires play a crucial role in the ignition process. Over time, they can become worn or damaged, leading to misfires and other issues that could trigger a P0351 code. Regularly inspecting these components and replacing them when needed can help prevent problems.

Clean or replace coils as needed

Ignition coils can also fail over time due to wear or damage. If you notice any signs of trouble with your coil(s), such as rough idling or poor performance, have them inspected by a qualified mechanic right away. Replacing faulty coils promptly can help avoid further damage to other parts of the ignition system.

Avoid harsh driving conditions

Driving on rough roads or in extreme temperatures can put additional stress on your vehicle’s ignition system. Whenever possible, try to avoid these types of conditions that could cause damage.

By following these tips and staying up-to-date on routine maintenance tasks for your vehicle’s ignition system, you may be able to prevent future occurrences of the P0351 code – saving you time and money in repairs down the line!


In conclusion, the P0351 code is a common issue that affects many vehicles. It indicates a problem with the ignition coil circuit in cylinder 1. This can lead to engine misfires, reduced power and fuel economy, and possible damage to other components.

If you have experienced any of these symptoms or have noticed the check engine light on your dashboard, it is important to have your vehicle inspected by a qualified mechanic. They will be able to diagnose the underlying cause of the P0351 code and recommend appropriate repairs.

Common causes of this error include faulty ignition coils, damaged wiring or connectors in the ignition system, or issues with the PCM (powertrain control module). Depending on what is causing this fault code to appear, repairs can range from simple fixes like replacing an ignition coil to more complex procedures such as rewiring components of your car’s electrical system.

It is important not to ignore any signs that something may be wrong with your vehicle’s engine. The longer you wait before having it repaired could result in further damage and higher repair costs down the line. By addressing problems promptly when they arise, you can help ensure that your car stays running smoothly for years to come.

Overall, if you are experiencing any issues related to P0351 code don’t hesitate contact an expert technician for assistance right away!

Click to comment

Leave a Reply

Your email address will not be published. Required fields are marked *

Recent comments

About us is an online resource with guides & diagrams for all kinds of vehicles. If you look for a fuse box diagram, timing belt diagram, or maybe wiring diagram – this is a place for you. We also have over 350 guides & DIY articles about cars.


Copyright © 2015-2023