P0301

What P0301 means

P0301 identifies cylinder #1 specifically. Pair it with P0300 or other cylinder-specific codes to see the full misfire pattern.

Symptoms

• Check engine light (often flashing)
• Rough idle
• Loss of power
• Vibration at idle

Likely causes (most common first)

1. Failed ignition coil on cylinder 1
2. Worn or fouled spark plug on cylinder 1
3. Clogged or dead fuel injector on cylinder 1
4. Low compression on cylinder 1 (bent valve, worn rings)
5. Wiring fault to the coil or injector

Can I keep driving?

High — risk of damage if ignored

Typical repair cost

DIY fixes can start near $40 (parts only). Shop repairs for P0301 typically run up to $800 depending on the underlying cause and vehicle. Start with the most common cause — Failed ignition coil on cylinder 1 — before throwing parts at it.

Symptoms that match P0301

If you got here from a search query, one of these might describe what your car is actually doing:

• Check Engine Light Flashing — What It Means and What to Do
• Rough Idle — Causes & How to Fix It
• Engine Misfire — Symptoms, Codes, and What to Fix First
• White Smoke from Exhaust — What It Means
• Blue Smoke from Exhaust — Engine is Burning Oil
• Engine Knocking Noise — Spark Knock vs Rod Knock

Recommended parts & tools for P0301

Compare the parts and tools that pair with AXLY:

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Related codes

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