P0304
P0304 — Cylinder 4 Misfire
1
Driver reports
1
Solved cases
1
Verified fixes
0
Wrong repairs reported
📊 Diagnostic Overview
Severity, cost and difficulty for P0304, based on data already on this page.
Severity
🟠 High
Diagnostic Difficulty
Not enough data yet
System
Engine
Common Causes (based on confirmed repairs)
- Cylinder-specific misfire (P0304 = cyl 4): Swap test method — move coil from cylinder 4 to cylinder 2. If code changes to P0302, the coil is bad. If P0304 stays on cylinder 4, try swapping spark plug. If still P0304 after coil and plug swapped, suspect in 1 vehicle
📐 Diagnostic Difficulty reflects how many different repairs drivers have tried for P0304 and how often those attempts turned out to be the wrong fix — it is calculated from MyCarFault's own reports, not an official manufacturer rating.
⭐ MOST VERIFIED FIX FOR P0304
Cylinder-specific misfire (P0304 = cyl 4): Swap test method — move coil from cylinder 4 to cylinder 2. If code changes to P0302, the coil is bad. If P0304 stays on cylinder 4, try swapping spark plug. If still P0304 after coil and plug swapped, suspect in
Reported in 1 approved case
·
⚪ Unverified
Top Reported Fixes for P0304
Ranked by confidence score — same vehicle matches weighted higher.
Driver Reports — P0304 1 report
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