The Lemon IndexCylinder 4 is not firing properly, so the engine runs rough and loses some power. Full P0304 page
10 owner complaints · the #4 code Kia Sorento owners name · 7% of Kia Sorento complaints that name a code (every car: 2.4%)
2013–2025 Kia Sorento · most: 2020 (2), 2014 (2), 2013 (2)
Kia Sorento owners named P0304 in 10 complaints to the U.S. government (NHTSA), most often on the 2020, 2014 and 2013 model years. The part they name most is the spark plugs (6 complaints). Complaints are owner reports, not proof of a defect.
Kia Sorento model years that report P0304
Owner complaints naming P0304, by model year. Raw counts: years that sold more get more complaints, so this is each model year's record, not a failure rate.
What owners say caused it or fixed it
The most-named part is the spark plugs, in 6 of the 10 complaints (60%). 6 of those mention it being replaced or repaired, and 3 say the problem came back afterwards. Next: ignition coils (3), fuel injectors (3) and engine (replaced or rebuilt) (2).
- Spark plugs6 complaints6 mention a repair or replacement, 3 of them say the problem came back · what owners paid
- Ignition coils3 complaints3 mention a repair or replacement, 2 of them say the problem came back · what owners paid
- Fuel injectors3 complaints2 mention a repair or replacement, 1 of them says the problem came back · what Kia Sorento owners paid
- Engine replaced or rebuilt2 complaints2 mention a repair or replacement, 2 of them say the problem came back · what Kia Sorento owners paid
- Fuel pump2 complaints2 mention a repair or replacement, 1 of them says the problem came back · what Kia Sorento owners paid
Counted from the owners' own words: a part counts when a sentence names it with a cause or repair word. What owners wrote, not a diagnosis. A shop should confirm the cause before replacing parts.
Symptoms owners describe with P0304
60% of these complaints say the check engine light came on.
- Shakes, runs rough or misfires70%7 of 10 complaints
- Stalls or shuts off30%3 of 10 complaints
- Loses power or goes into limp mode30%3 of 10 complaints
- Rattles or knocks20%2 of 10 complaints
- Flashing check engine light20%2 of 10 complaints
Share of the complaints naming P0304 whose text also describes each problem. A complaint can describe more than one.
Codes owners report with it
P0300 4 P0301 4 P0306 3 P0302 3 P0305 2 P0087 2
Other codes named in the same Kia Sorento complaints, and in how many.
Repair costs
Kia Sorento fuel injector replacement cost · Kia Sorento engine replacement cost · Kia Sorento fuel pump replacement cost
Recalls on these Kia Sorento years
- Engine · 2025 · issued 2025
The connecting rod bolts in the engine may have been improperly tightened, which can cause a loss of drive power. NHTSA 25V548000 - Engine · 2022 · issued 2022
The oil supply pipe to the turbocharger may crack, which could result in an oil leak in the engine compartment. NHTSA 22V202000 - Engine · 2013 · issued 2020
An engine compartment fire can occur while driving. NHTSA 20V750000 - Fuel system, gasoline · 2013, 2014, 2016 · issued 2018
The high pressure fuel pipe that connects to the fuel pump outlet may have been damaged, misaligned or improperly torqued during the engine replacement procedure, possibly causing a fuel leak. NHTSA 18V907000 - Engine · 2013, 2014 · issued 2017
Machining errors during the engine manufacturing process may cause premature bearing wear within the engine. NHTSA 17V224000
5 recalls for the same systems (engine and fuel) on the Kia Sorento model years above. A recall for the same system isn't proof it's behind P0304. Recall work is free at any dealer: check a VIN at nhtsa.gov/recalls or with our VIN check.
Keep going
- P0304: meaning, causes and every car that reports it
- Kia Sorento reliability by year
- 2020 Kia Sorento problems and recalls
Other codes Kia Sorento owners report
P0304 on other cars
Ford Escape (49) · Ford Edge (31) · Honda CR-V (23) · Honda Accord (20) · Honda Odyssey (19) · Ford Fusion (16) · Honda Pilot (14)
The details
How we count
We read every owner complaint in the NHTSA file whose text names this trouble code, and count the ones filed about this model (matched by the make, model and model year on the complaint). Mileage is what the owner entered on the form.
Parts: a complaint counts for a part when one of the owner's own sentences names that part together with a cause word (failed, bad, diagnosed, caused by, leaking ...) or a repair word (replaced, repaired, new, reprogrammed ...). "Came back" means the same complaint also says the problem returned or the repair didn't fix it. These are counts of what owners wrote, not a diagnosis, and one complaint can name several parts.
Complaints are reports, not proof of a defect, and most owners never file one. Popular models get more complaints, so the counts are not a failure rate. The code meaning is the standard SAE J2012 definition in our own words, or the carmaker's meaning where we verified it for that make.
What P0304 means
Cylinder 4 is not firing properly, so the engine runs rough and loses some power. A flashing check engine light means the misfire is serious enough to damage the catalytic converter, so slow down and get it checked right away.
Get it fixed soon. A few more days of normal driving is usually OK, but waiting can turn a small repair into a bigger one or a breakdown.
- Spark plug or ignition coil on cylinder 4
- Fuel injector on cylinder 4
- Vacuum leak near that cylinder
- Low compression (valve or piston ring problem)
Check the complaints yourself
NHTSA complaint numbers (search them at nhtsa.gov): 11723839, 11717128, 11713531, 11702272, 11685959, 11610947, 11513767, 11499800, 11425691, 11398161.
Quick answers
What does P0304 mean on a Kia Sorento?
Cylinder 4 Misfire Detected. Cylinder 4 is not firing properly, so the engine runs rough and loses some power. A flashing check engine light means the misfire is serious enough to damage the catalytic converter, so slow down and get it checked right away.
Which Kia Sorento years have the most P0304 complaints?
In complaints to NHTSA, owners of the 2020 (2), 2014 (2), 2013 (2) Kia Sorento named P0304 most (10 complaints in all, 2013–2025). Raw counts, not a failure rate.
What fixes P0304 on a Kia Sorento?
Owners most often name the spark plugs (6 of 10 complaints), then ignition coils and fuel injectors. That's what owners wrote, not a diagnosis: have a shop confirm the cause with a scan and tests before replacing parts.
Can I drive my Kia Sorento with P0304?
Get it fixed soon. A few more days of normal driving is usually OK, but waiting can turn a small repair into a bigger one or a breakdown.
Sources: NHTSA owner complaints that name P0304 on the Kia Sorento, counted by The Lemon Index; NHTSA recalls; repair bills owners named. Meanings: SAE J2012 in our own words. Owner reports, not a diagnosis or repair advice for your car.