2021-2022 Hyundai P2074 MIL & Engine Performance TSB

Certain 2021-2022 Hyundai Tucson, Santa Fe, and Sonata vehicles equipped with a 2.5L engine may experience a 'Check Engine' light (MIL) illuminated on the dashboard. This condition, often accompanied by diagnostic trouble code (DTC) P2074, can also lead to reduced engine performance and a limited power reduction mode.

This issue is addressed by a manufacturer communication, NHTSA ID 10206359, which outlines an Engine Control Module (ECM) software revision. This update aims to improve the logic for accurately detecting the amount of air the engine receives, resolving the underlying cause of the Hyundai Tucson P2074 and related DTCs.

Symptoms

Owners of affected vehicles may observe the following symptoms:

• Illumination of the 'Check Engine' light (MIL).
• Reduced engine performance, feeling sluggish or less responsive.
• The vehicle entering a limited power reduction mode, restricting available power.

Fault Codes / DTCs

When scanned, the vehicle's Engine Control Module (ECM) may store one or more of the following diagnostic trouble codes (DTCs):

Code	Description	Module
P2074	Mass Airflow Sensor Plausibility	ECM
P2074F0	Manifold Absolute Pressure/Mass Air Flow - Throttle Position Correlation at Lower Load	ECM
P2074F1	Manifold Absolute Pressure/Mass Air Flow - Throttle Position Correlation at Medium or High Load	ECM
C136081	ESP Irreversible Error	ESP
C161308	CAN Signal Error EMS	EMS
C161386	CAN Signal Error EMS	EMS
C169381	Blind-Spot Collision Warning – CAN signal failure - ESC	ESC
C174181	ESC Not Available VSM (Check ESC)	ESC
C183586	CAN Message Failure ESC/IEB	ESC

Diagnosis and Trigger Conditions

This condition is primarily triggered by an inaccuracy in the Engine Control Module (ECM) software. The original software may not correctly interpret the air intake data, leading to the system misidentifying a problem and setting the Hyundai Tucson P2074 code. This can occur under various load conditions, as indicated by the P2074F0 and P2074F1 sub-codes.

Secondary DTCs related to the Electronic Stability Program (ESP), Electronic Stability Control (ESC), and Controller Area Network (CAN) communication may also be stored as a consequence of the primary engine control issue.

Repair Procedure Summary

The recommended repair involves updating the Engine Control Module (ECM) software. This software revision will update the logic to accurately detect the amount of air the engine is receiving, thereby preventing the erroneous setting of DTC P2074 and resolving the associated performance issues.

Owner Action

If your 2021-2022 Hyundai Tucson, Santa Fe, or Sonata with a 2.5L engine is exhibiting a 'Check Engine' light with symptoms of reduced engine performance, it is recommended to visit an authorized Hyundai dealership. Inform them about the symptoms and the potential relevance of manufacturer communication NHTSA ID 10206359. The dealership technicians can diagnose the issue and perform the necessary ECM software update.

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Source: NHTSA ID 10206359