P0351
Fix within a few daysThe engine computer detects a problem with the electrical circuit for the ignition coil on cylinder #1.
Code P0351 means the engine computer detects an issue with cylinder 1's ignition coil circuit. Common causes: Faulty ignition coil (70%), wiring issues (20%). Drivability: Limit driving, fix within a few days. Repair cost: $50-$200 DIY, $150-$500 professional.
Can I Drive With P0351?
Limit driving, fix within a few days
Essential trips under 10 miles, avoid highways and heavy acceleration. Do not drive if the Check Engine Light is flashing.
Stop driving immediately if: Flashing Check Engine Light, significant power loss, loud engine noises, or a strong smell of raw fuel.
Symptoms of P0351
- 1Check Engine Light is on (may flash during misfire)
- 2Engine misfires or runs rough
- 3Reduced engine power
- 4Engine hesitation or stumbling during acceleration
- 5Poor fuel economy
Common Causes of P0351
Parts most likely causing this code, ranked by probability
The ignition coil for cylinder #1 is faulty and cannot generate or deliver the proper spark.
70% of P0351 cases are fixed by replacing this part
Damaged, corroded, or loose wiring to the ignition coil prevents proper electrical signal flow.
20% of P0351 cases are fixed by repairing wiring or connector
A severely worn, fouled, or damaged spark plug can cause the ignition coil to overwork and appear faulty.
5% of P0351 cases are fixed by replacing this part
An internal fault within the engine computer prevents it from properly controlling the ignition coil circuit.
5% of P0351 cases are fixed by replacing this part
Check These First (Before Buying Parts)
- Visually inspect the ignition coil and its electrical connector for cylinder #1 for any obvious damage or loose connections.
- Swap the ignition coil from cylinder #1 with a coil from a different cylinder (e.g., cylinder #2). Clear the code and see if the P0351 code moves to the new cylinder (e.g., P0352).
How to Diagnose P0351
- 1Check for other related misfire codes (P0301).
- 2Visually inspect the ignition coil and its electrical connector for cylinder #1 for any damage, corrosion, or loose connections.
- 3Swap the ignition coil from cylinder #1 with a known good coil from another cylinder (e.g., cylinder #2). Clear the code and see if the code moves to the new cylinder (e.g., P0352).
- 4Remove and inspect the spark plug for cylinder #1 for wear, fouling, or damage. Replace if necessary.
- 5Using a multimeter, test the power, ground, and signal wires at the ignition coil connector for cylinder #1 according to your vehicle's service manual.
- 6If all other components check out, consider testing or replacing the Engine Control Module (ECM/PCM).
P0351 on Popular Vehicles
Toyota Camry
2002-2024Ignition coil failures are common on these models, especially after 100,000 miles. The coils are easily accessible for replacement.
75% fixed by replacing ignition coil
Honda Accord
2003-2024Similar to Camry, Honda Accord models frequently experience ignition coil failures. Check for oil leaks around the spark plug tubes that can contaminate the coil.
70% fixed by replacing ignition coil
Ford F-150
2004-2024Ford F-150s, particularly those with V8 engines, are notorious for ignition coil failures. The coils are often referred to as 'coil-on-plug' units and are a common maintenance item.
80% fixed by replacing ignition coil
Frequently Asked Questions
What does P0351 mean?
P0351 indicates that the engine's computer has detected an electrical malfunction in the primary or secondary circuit of the ignition coil for cylinder #1. This means the coil is not receiving or sending the correct electrical signals.
Can I drive with P0351?
Limit driving, fix within a few days. If the Check Engine Light is flashing, stop driving immediately. A flashing light indicates a severe misfire that can rapidly damage your catalytic converter. If it's solid, you can drive short distances, but expect reduced power and fuel economy.
Will P0351 clear itself?
No, P0351 will not clear itself. The engine computer stores this code until the underlying electrical issue with the ignition coil circuit is repaired. You will need to fix the problem and then clear the code with a scan tool.
How do I fix P0351 myself?
Start by visually inspecting the ignition coil and its connector for cylinder #1. If no obvious damage, swap the coil with another cylinder's coil to see if the code moves. If it does, replace the ignition coil for cylinder #1. If the code stays, inspect the spark plug and then test the wiring to the coil.
How much does it cost to fix P0351?
The cost to fix P0351 varies. DIY repair, primarily replacing the ignition coil, costs $50-$150 for the part. Professional repair at a shop typically costs $150-$500, including parts and labor, depending on the vehicle and shop rates.
P0351 keeps coming back - why?
If P0351 keeps returning, it indicates the initial repair did not address the root cause. Common reasons include a faulty spark plug, damaged wiring to the coil, a problem with the engine computer (ECM/PCM), or a new coil that was defective out of the box.
Will P0351 fail emissions/smog test?
Yes, P0351 will cause your vehicle to fail an emissions or smog test. Any active Check Engine Light, especially one related to ignition or misfires, prevents the vehicle from passing inspection.
What's the difference between P0351 and P0301?
P0351 specifically indicates an electrical circuit malfunction with the ignition coil for cylinder #1. P0301 indicates a general misfire detected in cylinder #1. P0351 is a more specific diagnostic code that often causes a P0301 misfire code.
P0351 on Ford F-150 - what's common?
On Ford F-150s, especially those with Triton engines, P0351 is very common and almost always points to a failed ignition coil on cylinder #1. The coils are known to fail, particularly with age and mileage. It's a straightforward replacement.
Questions to Ask Your Mechanic
Did you swap the ignition coil from cylinder #1 to another cylinder to confirm the coil is faulty?
Good answer: Yes, we swapped the coil to cylinder #3, and the code changed to P0353, confirming the coil is bad.
Did you check the wiring and connector for cylinder #1's ignition coil for power, ground, and signal?
Good answer: Yes, we tested the circuit and confirmed proper voltage, ground, and PCM signal to the coil.
Repair Cost Estimate
DIY Repair
Parts only
$50-$150
Shop Repair
Parts + labor
$150-$500
Save $100-$350 by doing it yourself
Difficulty
beginner
Time
0.5-1 hours
Beginner-friendly - Replacing an ignition coil is one of the easiest DIY repairs. Diagnosing wiring issues requires intermediate skills and a multimeter.
Cost of Waiting
Continued misfires send unburned fuel into your exhaust system, which can rapidly overheat and destroy your catalytic converter. A $50-$150 ignition coil job now prevents a $800-$2,500 catalytic converter replacement later.
While You're In There...
If one spark plug is worn enough to cause a coil issue, the others are likely due for replacement. Replacing them now prevents repeat labor.
These rubber boots and connectors can degrade over time, leading to poor electrical contact or moisture intrusion. Replacing them with the coil ensures a solid connection.
Tools You'll Need
- OBD-II Scan Tool
- Socket Wrench Set
- Spark Plug Socket (if checking plug)
- Screwdriver Set
- Dielectric Grease
P0351 is a common ignition system code. Most repairs involve replacing a single ignition coil, which is a straightforward fix that will get your engine running smoothly again.
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Your Next Steps
Step 1: Perform the coil swap test. Move the cylinder #1 coil to another cylinder. If the code follows the coil, replace the faulty ignition coil.
Step 2: If the code does not follow the coil, remove and inspect the spark plug for cylinder #1. Replace if worn or fouled.
Step 3: If the coil and spark plug are good, use a multimeter to test the wiring harness to the cylinder #1 ignition coil for proper power, ground, and signal from the ECM/PCM. Repair any damaged wiring.