2005 Subaru Sti: Cel P0304 Code. Safe To Drive? How Fix Cylinder 4 Misfire Diagnosis & Repair Guide

Author Dalbo 03 May 2026

Is it safe to continue driving my subaru with code p0304 if the engine is running smoothly despite the error code The p0304 engine code can compromise your driving. P0304 means cylinder 4 is misfiring

Comprendre le code d’erreur P0304 : causes, conséquences et solutions

2005 Subaru Sti: Cel P0304 Code. Safe To Drive? How Fix Cylinder 4 Misfire Diagnosis & Repair Guide

Learn symptoms, common causes, diagnosis steps, proven fixes, repair cost ranges, plus trusted external resources for deeper help. Some common symptoms of the p0304 code are an illuminated check engine light, rough idling, and excessive fuel consumption Diagnostic trouble code (dtc) p0304 stands for “cylinder 4 misfire detected.” the code indicates that the powertrain control module (pcm) has counted enough misfire events on cylinder 4.

If your check engine light is flashing, stop driving immediately — unburned fuel is damaging the catalytic converter

Even with a steady light, prolonged driving increases the risk of converter damage and. Learn what triggers the p0304 cylinder 4 misfire code, how to diagnose it, and the best ways to fix it before costly damage occurs. Discover the common causes of the p0304 diagnostic trouble code and learn how to troubleshoot a misfire in cylinder 4 of your engine. Has anyone encountered code “p0304 with u0122” was driving fine on highway then out of nowhere car started to sound like a hot rod and cel came on.