P0301 on Buick
Cylinder 1 Misfire Detected
P0301 on Buick vehicles indicates cylinder 1 misfire detected. Au7o has documented this code across 2 Buick models — most commonly on Lucerne, Regal. P0301 means the engine computer detected a misfire specifically in cylinder 1 — the spark didn't ignite the fuel properly, or the fuel/air mix didn't burn as it should. The computer detects this by sensing tiny variations in crankshaft speed each time a cylinder fires. A misfire wastes fuel, raises emissions, and can damage the catalytic converter if it's severe or persistent (a flashing check engine light usually warns of active, converter-damaging misfires). Because the code points to one specific cylinder, the cause is usually an ignition, fuel, or compression problem isolated to that cylinder. Typical repair costs on Buick range from $400 to $7,500, depending on the specific model and root cause.
Common Causes of P0301
- •Worn or fouled spark plug in cylinder 1
- •Failed ignition coil or coil pack for cylinder 1
- •Faulty or clogged fuel injector for cylinder 1
- •Vacuum or intake air leak affecting that cylinder
- •Bad spark plug wire (on applicable engines)
- •Low compression (worn rings, leaking or burnt valve, head gasket)
- •Carbon buildup on intake valves
- •Wiring or connector fault to the coil or injector
P0301 on Buick by Model
Buick Lucerne(1 issue)
- Lucerne Northstar V8 Head Bolt Pull / Coolant Loss2006-2011
The 4.6L Northstar V8 in 2006-2011 Lucerne CXS/Super (and STS, DTS, Cadillac SLS) is known for head-bolt thread pull from the aluminum block. Bolts back out of the block (rather than head gasket failing outright), allowing combustion gases into the coolant. Symptoms: coolant loss, white smoke, overheating, eventually no-start.
Buick Regal(1 issue)
- Carbon Buildup on Intake Valves (Direct Injection)2011-2017
Like other GM direct-injected engines, the Regal's 2.0T and 2.4L DI engines accumulate carbon deposits on the back of the intake valves because fuel no longer washes the valves clean. Over tens of thousands of miles this causes cold-start misfires, rough idle, hesitation, and reduced power and economy. It is a well-documented owner complaint on the turbo cars in particular.
Looking for P0301 on a different make?
View P0301 across all makes →Frequently Asked Questions
What does P0301 mean on Buick?▼
P0301 stands for "Cylinder 1 Misfire Detected." P0301 means the engine computer detected a misfire specifically in cylinder 1 — the spark didn't ignite the fuel properly, or the fuel/air mix didn't burn as it should. The computer detects this by sensing tiny variations in crankshaft speed each time a cylinder fires. A misfire wastes fuel, raises emissions, and can damage the catalytic converter if it's severe or persistent (a flashing check engine light usually warns of active, converter-damaging misfires). Because the code points to one specific cylinder, the cause is usually an ignition, fuel, or compression problem isolated to that cylinder. On Buick specifically, this code is documented across 2 models.
What causes P0301 on Buick vehicles?▼
Common causes on Buick: Worn or fouled spark plug in cylinder 1, Failed ignition coil or coil pack for cylinder 1, Faulty or clogged fuel injector for cylinder 1, Vacuum or intake air leak affecting that cylinder, Bad spark plug wire (on applicable engines). Specific causes vary by model and year — see the per-model sections below.
How much does it cost to fix P0301 on a Buick?▼
Repair costs on Buick range from $400 to $7,500, depending on the specific model and root cause.
Which Buick models have P0301 documented?▼
Au7o has documented P0301 on 2 Buick models: Lucerne, Regal.