What are the symptoms of P0301?

Common symptoms include: Rough idle; Vibration; Power loss; Smoke.

What causes a P0301 code?

The most common causes are: Faulty injector on that cylinder; Low compression in that cylinder; Glow plug failure (cold); Wiring to that injector.

How do you fix P0301?

Compare cylinder contribution data; Compression-test the affected cylinder; Swap/test the injector to confirm. Take this seriously. It can trigger a power derate or lead to damage if you keep driving — get it diagnosed promptly.

OBD-II Code Lookup

P0301Serious

Cylinder 1 Misfire Detected

Engine system

A misfire isolated to cylinder 1. (P0302–P0308 are the same fault on cylinders 2–8.) A single-cylinder misfire narrows the search to that cylinder's injector, compression, or fuel delivery.

Take this seriously. It can trigger a power derate or lead to damage if you keep driving — get it diagnosed promptly.

Common symptoms

Rough idle
Vibration
Power loss
Smoke

Common causes

Faulty injector on that cylinder
Low compression in that cylinder
Glow plug failure (cold)
Wiring to that injector

How it's diagnosed & fixed

Compare cylinder contribution data
Compression-test the affected cylinder
Swap/test the injector to confirm

Got P0301? Get it diagnosed.

A real technician can interpret P0301 in the context of your truck and symptoms — and tell you what's actually wrong before you buy parts.

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Related Engine codes

P0300Random/Multiple Cylinder Misfire Detected

Reference only. A trouble code names a symptom, not the failed part — always confirm with a live diagnosis before repairs. See our Knowledge Base for deeper guides.