Vauxhall P0301

Cylinder 1 misfire on Vauxhall — A14NET coil pack and Z19DTH injector cyl 1 wear.

Vauxhall P0301 — Cylinder 1 misfire on Vauxhall — A14NET coil pack and Z19DTH injector cyl 1 wear. Typical UK independent garage cost: £70–£500.

What actually causes P0301 on a Vauxhall

Vauxhall P0301 — coil pack on A14NET (very common), injector wear on Z19DTH. Always swap-test before condemning.

Vauxhall engines that log P0301

• 1.4 Turbo A14NET (Astra J/Corsa E)
• 1.6 SIDI A16XER
• 1.9 CDTi Z19DTH

How we diagnose P0301 on a Vauxhall

1. Swap coil 1↔2
2. Injector correction read on diesel
3. Spark plug condition
4. Compression test if mechanical

The common misdiagnosis to avoid

Cheap coil packs on A14NET fail again within months — Delphi/Bosch OE only.

Vauxhall P0301 repair cost in the UK

Expect £70–£500 including parts and labour at an independent garage. Main-dealer quotes on Vauxhall are usually higher for the same job, and the spread exists because the cheap cause and the expensive cause throw the same code — pay for the diagnosis before you pay for parts.

Bob's workshop tip

Astra A14NET P0301 — Bosch coil, OEM spec. Don't cheap out.

Codes usually seen alongside P0301 on Vauxhall

• P0300
• P0302
• P0303
• P0304

Symptoms drivers report with P0301

• Engine 'juddering' like a wet dog when you try to overtake on the A9.
• The car 'kangaroos' at low speeds, especially when the engine is stone cold.
• The EML (Engine Management Light) is flashing at you—that's a 'stop now' warning for your catalytic converter.
• A distinct 'put-put-put' sound from the exhaust pipe at idle.
• Massive loss of power, feels like you're towing a caravan that isn't there.

Repairs that clear P0301

• Replace spark plug
• Swap coil pack
• Injector test
• Compression test

For the generic, all-makes explanation of this code — meaning, every known cause and UK cost bands — see our P0301 guide.

Reading P0301 on a Vauxhall properly

A generic reader will show P0301 and nothing else. What matters is the freeze-frame data stored with it — engine speed, load, coolant temperature and fuel trims at the moment the fault was logged — plus whether any other module on the Vauxhall has logged something at the same time. Codes rarely arrive alone, and the order they were stored in usually points at which one is the cause and which are the consequences.

Clearing P0301 without fixing it

Erasing the code resets the Vauxhall's readiness monitors as well as the light. The fault returns on the next drive cycle if the cause is still there, and in the meantime the incomplete monitors can stop the car passing an emissions check. After a genuine repair, the car is driven until the relevant monitor completes before it is handed back.

Bob's Mechanical Repairs is an independent garage in Birnam, Dunkeld, Perthshire, with 32 years of Bob's experience on the tools. If P0301 is showing on your Vauxhall, bring any scan results with you — we will read the live data ourselves, confirm which cause it actually is, and price the repair before any work starts.