P0304 on Kia vehicles
31 owner complaints filed with NHTSA about Kia vehicles mention P0304 (Cylinder 4 Misfire Detected) - across 9 models. Below is where it shows up, by model and year.
Can you drive with it? Short careful trips only while the light stays steady. If it starts FLASHING, stop as soon as it is safe - that is the computer reporting active catalyst-damaging misfire, not a suggestion.
Symptoms, likely causes in order and realistic repair costs are on the main P0304 page - they do not differ much by brand. This page shows what is specific to Kia: which models and years actually report it.
Kia models reporting P0304
The number next to each year is how many NHTSA complaints for that car mention P0304. Owners rarely quote trouble codes when complaining, so real occurrence is many times higher - use these numbers to compare years, not as totals.
What Kia owners report
“I will be accelerating and the car will on occasion start to sputter like it is going to die and loose power on me. It has done it three different times the last time it through a code on my OBD monitor read it and said P0304 the 4th cylinder is misfiring. I took it in and they couldn't see the code or even the history of there being a code thrown. Please help my ladst car that did this needed to have the engine replaced and is recall was issued after we sold it to a junk yard, and I can't afford that again.”2023 Kia Soul · Sep 2026
P0304 on other makes
Makes with enough NHTSA reports of P0304 for their own page.
Counts are NHTSA owner complaints whose text mentions P0304 - owner-reported and unverified. Always confirm with a diagnosis of your specific vehicle.