Why does my Kia Stinger GT misfire when I get on it?

Short answer: On the Stinger's 3.3L twin-turbo V6, a misfire under hard acceleration is most often a worn or wrongly gapped spark plug, and sometimes an ignition coil. Turbo engines need a tighter plug gap. If several cylinders on the same side misfire, or it stalls or goes into limp mode, don't assume plugs: owners have found valve problems. Get the codes read before buying parts.

Symptom: A stutter or jerk at full throttle; the check engine light flashing; codes like P0300 (random misfire) or P0306 (cylinder 6); in worse cases limp mode or stalling.

What to check first

1. Read which cylinders are misfiring. One cylinder points to a plug or coil. Several on one side (bank) points elsewhere.
2. Swap the coil to another cylinder. If the misfire moves, the coil is bad.
3. Check the plugs and gap. Owners say gap them tight, about 0.024 inch, on this engine.
4. Use premium fuel and avoid lugging the engine at high boost in a low gear.
5. If several cylinders on one bank misfire or it stalls, get a compression and leak-down test.

Likely causes

1. Worn or wrongly gapped spark plugs. The most common fix owners report.
2. Failed ignition coil. Some owners needed coils after plugs.
3. Valve or other internal engine problem. One owner's misfires turned out to be a bad exhaust valve.

What it usually costs

One owner said Denso plugs were about $12 each versus $50–$60 from his dealer, plus about $225 to install one plug. Another said a coil is a $400–$600 part. Prices are from owner posts.

Is it safe to keep driving?

A flashing check engine light means back off and get it fixed soon, because heavy misfires can damage the catalytic converter. If it stalls or goes into limp mode, stop driving it and get it to a dealer. Verify with a mechanic.

DIY or shop?

DIY for plugs and coils for experienced owners. Internal engine work is a shop job, and often a warranty claim.

Recalls, bulletins and complaints in plain words

• Related recalls: NHTSA lists these recalls touching this area of the Kia Stinger: 24V169000 (2018-2023 model years, engine and engine cooling). Check your VIN at nhtsa.gov/recalls. If your car is part of this recall, the dealer fixes it for free.
• NHTSA complaints: 32 keyword-matched complaints for Kia Stinger 2018–2023 (of 169 unique complaints queried, NHTSA complaints API by model year, queried 2026-10-23; keywords: misfire, spark plug, ignition coil, stall, engine). This counts complaints that mention these words. It is not a defect finding.

What owners report

• In 3.3TT Cylinder #6 Misfire on Kia Stinger Forum, a 2019 GT2 owner had a second misfire after the dealer replaced one plug. Members recommended Denso plugs gapped to about 0.024 inch across all cylinders and said a coil should be next if a new plug doesn't fix it. One owner said he blew the same plug again driving off the lot.
• In Can spark plugs cause misfire only under load?, an owner with P0300 replaced and gapped plugs and still had hesitation until coils were replaced. Another's misfires kept moving cylinders until Kia replaced all plugs and all coils under warranty.
• In 2019 Kia Stinger GT 3.3TT — misfires, limp mode, and possible engine replacement, an owner at about 74,000 miles had misfires on cylinders 1, 3 and 5, then limp mode and a stall. New plugs and coils didn't help; a leak-down test found a bad exhaust valve, and Kia approved a cylinder head repair under the powertrain warranty.

Quick tip

Start with properly gapped plugs. If the misfire is on several cylinders on one side, push for deeper testing while you're still under warranty.

Vehicle focus: 2018–2023 Kia Stinger GT with the 3.3L twin-turbo V6. The 2.0T and 2.5T four-cylinders are different.

Safety / mechanic note

A heavy misfire or stall can leave you without power in traffic. Verify with a mechanic.