P0204 OBD-II code — what it means and what to check

ℹ Guidance only — not a substitute for inspection

Enter the trouble codes from your scanner to see what each one means, how urgent it is, and which checks to do first.

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Your trouble codes

Enter the codes exactly as your scanner shows them. Separate several codes with spaces or commas.

A letter followed by four characters, for example P0301. Up to ten codes at a time.
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Your codes, interpreted

What this means
⚠ Have this looked at now. At least one code you entered should not be left until the next service.
What to doArrange a workshop inspection now, and keep journeys short and local until then.

Your codes

  1. P0204 — Fuel and air metering (service now). The fuel injector circuit for cylinder 4 is open or faulty. That cylinder may not be receiving fuel.

Checks to do first, in order

  1. Expect a misfire, rough running, and unburned fuel reaching the catalytic converter — do not run the engine longer than needed.
  2. Inspect the injector connector and wiring for cylinder 4; a disconnected or corroded connector is the most common cause.
  3. Measure the injector's coil resistance against specification.
  4. Swap the injector with a neighbouring cylinder to confirm before buying parts.

Codes this tool cannot interpret

How this result was reached
  • Interpretations cover standardised codes only, and describe what a code means rather than what is wrong with your specific vehicle.
  • A stored code identifies the circuit or system reporting a fault. It does not identify the failed part — a sensor commonly reports a problem it did not cause.
  • Reviewed by Project Owner on 2026-08-26.
  • This tool covers a reviewed subset of standardised codes. A code it does not recognise is reported as undocumented rather than guessed at.