2021-2023 Hyundai Misfire DTCs P0300-P0304 TSB
Hyundai Technical Service Bulletin 25-FL-001H details the replacement of GDI fuel injectors for 2021-2023 Santa Cruz, Santa Fe, Sonata, and Tucson models experiencing misfire diagnostic trouble codes P0300, P0301, P0302, P0303, P0304 due to internal leakage.
Also applies to
- Hyundai Santa Cruz
- 2022
- Hyundai Santa Fe
- 2021–2022
- Hyundai Sonata
- 2021–2023
- Hyundai Tucson
- 2023
Hyundai has issued Technical Service Bulletin (TSB) 25-FL-001H, dated January 2025, to address misfire diagnostic trouble codes (DTCs) that may appear in certain 2021-2023 models equipped with the 2.5L GDI Theta III non-turbo engine. This TSB supersedes the previous bulletin 23-FL-002H-1 and provides updated procedures for replacing all GDI fuel injectors, including revised parts information, warranty details, and service procedures.
The TSB explains that internal leakage within the GDI injectors, potentially caused by internal filter breakage, can lead to various misfire DTCs. If your vehicle exhibits a Hyundai Tucson misfire DTC P0300 or any other misfire code listed, this bulletin outlines the necessary repair.
Symptoms
Owners of affected Hyundai vehicles may notice their engine exhibiting one or more misfire diagnostic trouble codes. These codes indicate that one or more cylinders are not firing correctly, which can lead to rough idling, reduced engine performance, and potentially a check engine light illumination. If you experience a Hyundai Tucson misfire DTC P0300 or similar, it's important to have your vehicle inspected.
Fault Codes / DTCs
The following misfire DTCs are specifically addressed by TSB 25-FL-001H:
- P0300: Random/Multiple Cylinder Misfire Detected
- P0301: Cylinder 1 Misfire Detected
- P0302: Cylinder 2 Misfire Detected
- P0303: Cylinder 3 Misfire Detected
- P0304: Cylinder 4 Misfire Detected
Diagnosis / Trigger Conditions
Diagnosis for this issue involves performing a fault code search using a diagnostic tool. If one or more of the misfire DTCs (P0300, P0301, P0302, P0303, P0304) are found, and the vehicle falls within the applicable range listed in the TSB, then the GDI injector replacement procedure should be followed. If these specific DTCs are not present, or if the vehicle is not within the applicable range, this TSB does not apply, and normal diagnostic procedures should be used.
Important Warnings for Technicians and Owners
Hyundai provides several critical warnings within TSB 25-FL-001H to ensure proper repair and prevent damage:
Gallery
11 images
Frequently Asked Questions
- What does Hyundai TSB 25-FL-001H address?
- Hyundai TSB 25-FL-001H addresses misfire diagnostic trouble codes (DTCs) such as P0300, P0301, P0302, P0303, and P0304 in certain 2021-2023 Hyundai models with 2.5L GDI engines. The issue is caused by internally leaking GDI fuel injectors.
- Which Hyundai models are affected by this misfire issue?
- This issue affects 2021-2023 Hyundai Santa Cruz, Santa Fe, Sonata, and Tucson models equipped with the 2.5L GDI Theta III non-turbo engine. If you have a Hyundai Tucson misfire DTC P0300, your vehicle may be included.
- What is the repair for the GDI injector misfire problem?
- The repair involves replacing all four GDI fuel injectors using a specific kit (part number 35399-2S133QQH) and following the detailed procedure outlined in TSB 25-FL-001H. This includes cleaning cylinder head holes and carefully observing all torque specifications.
- Will I be charged for the GDI injector replacement under this TSB?
- The TSB indicates that claims should be submitted as 'Campaign' type. If the affected part is still under warranty, the repair should be covered. For parts out of warranty, a Prior Approval request for goodwill consideration may be necessary. Always confirm warranty coverage with your authorized Hyundai dealer.
What Hyundai Tucson owners report
Counted from the records in our database across 22 model years.
- 6,738
- Owner complaints
- 37
- Recalls
- 564
- Service bulletins
- 276
- Crashes reported
- 145
- Fires reported
- 256
- Injuries reported
The 2022 model year
509 complaints, the 3rd most of 22 model years on file. Owners reported 31 crashes, 5 fires and 56 injuries for this year, which also has 3 recalls on file.
Fuel/Propulsion System, the system this article covers, accounts for 424 of 6,738 complaints (6%), including 151 for 2022.
Complaints by model year
| 2012 | 255 | |
|---|---|---|
| 2013 | 266 | |
| 2014 | 202 | |
| 2015 | 229 | |
| 2016 | 1,626 | |
| 2017 | 1,095 | |
| 2018 | 399 | |
| 2019 | 385 | |
| 2022 | 509 | |
| 2025 | 451 |
Most-reported systems
- Engine — 2,451
- Power Train — 1,273
- Electrical System — 849
- Service Brakes — 761
- Forward Collision Avoidance — 432
Latest recalls for the 2022 model year
- 25V893000 — Trailer Hitches (Dec 2025) — Park outside
- 23V038000 — Structure (Jan 2023)
- 21V938000 — Electrical System (Dec 2021)
Recent owner reports about fuel/propulsion system
My car suddenly broke down on the side of a busy highway halfway through my workday. When attempting to restart it, all warning lights came on on the dashboard and I could see white smoke coming out of the exhaust pipe while the car shook.
Read owner complaints →Vehicle Fuel Injector code P053F84 Reading on 9/9/26, this is the second time vehicle was taken to the dealership for the exact same problem, the idle button in orange, and displayed, first visit while vehicle within warranty limits technician stated couldn't…
Complaints are owner reports filed with NHTSA. They are unverified, and counts depend on how many vehicles were sold, so they are not a failure rate.
Related Articles
2021-2024 Hyundai Santa Fe / Tucson DTC U028700 EOP
Hyundai has issued Technical Service Bulletin (TSB) 26-AT-002H for certain 2021-2024 Santa Fe and Tucson vehicles. This TSB addresses diagnostic trouble code U028700, indicating a "Lost Communication With Trans Fluid Pump Module," which can cause the Idle Stop & Go (ISG) system to become…
2022 Hyundai Tucson Inoperable Horn Warranty Extension
Hyundai has issued a warranty extension for certain 2022 Tucson (NX4A) vehicles experiencing an inoperable horn. This issue, detailed in TSB 26-BE-004H, is caused by foreign substances oxidizing internal horn parts. Coverage is extended to 10 years/120,000 miles.
2022 Hyundai Tucson Inoperative Horn TSB 26-BE-004H
Hyundai has issued Technical Service Bulletin 26-BE-004H for certain 2022 Tucson (NX4A) vehicles experiencing an inoperative horn. This TSB extends warranty coverage to 10 years/120,000 miles for horn replacement due to internal oxidation from foreign substances.
2021-2022 Hyundai Anti-Theft Ignition Cylinder Protector TSB
Hyundai has issued Technical Service Bulletin 25-01-089H (Customer Satisfaction Campaign P33) to address vehicle theft concerns by installing an anti-theft ignition cylinder protector and anti-theft decals on various 2021-2022 models.
2021-2022 Hyundai Anti-Theft Ignition Cylinder Protector Campaign P33
Hyundai has launched Customer Satisfaction Campaign P33 for 2021-2022 models, offering a free anti-theft ignition cylinder protector and decals. This hardware upgrade, detailed in TSB 25-01-089H, is available upon customer request to counter social media theft methods.
Leave a comment
Comments are moderated and may take a moment to appear. Only your first name and the initial of your last name are shown publicly.
Comments
Be the first to comment.