Kia check engine codes

Overview

Kia shares engines with Hyundai, including some Theta II engines covered by recalls and warranty extensions. Catalytic converter and EVAP codes are common.

Codes notably common on Kia

• P0420 Catalyst System Efficiency Below Threshold (Bank 1) · Kia notes
• P0300 Random or Multiple Cylinder Misfire Detected
• P0171 System Too Lean (Bank 1)
• P0442 Evaporative Emission System Small Leak Detected

Kia specific notes

• Kia extended engine coverage for connecting rod bearing failure on certain Theta II and other engines through class action settlements. A Knock Sensor Detection System update is generally required. Check your VIN with Kia and NHTSA.

Owner's manuals

Official Kia owner's manual / owner portal (manufacturer site; we do not host copies).

Recall lookup

Check open Kia recalls with your VIN at the NHTSA recall lookup.

Sources

• https://kiaengineclasssettlement.com/Home/FAQ
• https://www.nhtsa.gov/recalls

Sources checked October 2026. Bulletins apply only to the models and years they list.

All other codes

These work the same on Kia as on any vehicle:

P0430 P0301 P0302 P0303 P0304 P0174 P0440 P0455 P0456 P0128 P0135 P0141 P0101 P0299 P2135 P0401