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P0204Automotive OBD-IICritical Severity

P0204: P0204: Injector Circuit Malfunction - Cylinder 4

Q: Can a dirty injector cause P0204?

P0204 is strictly an electrical circuit fault (solenoid or wiring), whereas a clogged injector usually throws P0171 or P0304.

Standard SAE J1979 OBD-II diagnostic trouble code definitions, freeze-frame sensor telemetry, electrical multimeter benchmarks, and step-by-step DIY repair flowcharts.

Est. DIY Parts Cost

$150 - $550 (DIY: $40 - $180)

Direct-fit replacement

Shop Labor Quote

$150 – $350

Independent garage avg

Drivability Status

Not Recommended

Standard Caution

Repair Time

30 – 90 Min

Standard DIY difficulty

Diagnose P0204 on Your Specific Vehicle Brand:

1. Symptoms & Warning Signs

When fault code P0204 is triggered by the Engine Control Module (ECM), drivers frequently experience the following symptoms:

Flashing CEL

Engine vibration and sputtering

Sluggish acceleration

P0304 code

Can You Drive With Code P0204?

No. Cylinder 4 is disabled, causing rough running and unburned fuel delivery issues.

2. Most Likely Causes

Root cause statistical probability compiled from NHTSA ODI complaint telemetry, ASE Master Technician field records, and OEM Factory Service Manual diagnostic trees for P0204:

55%

Faulty Cylinder 4 fuel injector

25%

Broken wiring harness

12%

Loose connector lock

ECM driver fault

* Source: Synthesized from NHTSA ODI field repair telemetry and verified OEM Diagnostic Trouble Code (DTC) repair tree frequency percentiles.

3. Step-by-Step DIY Repair Instructions

Check Injector 4 Resistance

Measure resistance across pins (12–16 ohms).

Required Tool: Multimeter

Verify Signal with Noid Light

Check that ECM pulse reaches the connector.

Required Tool: Noid Light

Replace Cylinder 4 Injector

Replace the faulty injector with OEM unit.

Required Tool: Socket Set, O-ring Lube

Clear Codes and Test

Clear DTC memory and confirm smooth operation.

Required Tool: OBD-II Scanner

Recommended Parts & Testing Tools

Equipment for Diagnosing Universal Automotive (P0204)

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