Table 1 shows one common engine and engine cooling related problems of the 2020 Volkswagen Passat.
| Problem Category | Number of Problems |
|---|---|
| Engine And Engine Cooling problems |
2020 Volkswagen Passat se 2. 0l VIN: [xxx] complaint summary: I am reporting a persistent and unresolved fault involving the secondary air injection system (dtc p0491 – insufficient airflow) that has resulted in repeated, conflicting diagnoses across multiple repair facilities. This raises concerns about a potential systemic defect affecting this vehicle model. Detailed description: the issue began prior to March 2025 while the vehicle was still under warranty. The vehicle displayed a check engine light associated with diagnostic trouble code p0491 (secondary air injection system insufficient airflow). On April 3, 2025, a repair facility diagnosed the issue as a failed secondary air injection pump and replaced the component. However, the check engine light returned within 24 hours with the exact same fault code, indicating that the repair did not resolve the issue. A second independent diagnostic evaluation was performed later in April 2025. This inspection confirmed that: the secondary air injection pump was functioning correctly airflow through the system was present electrical controls and pcm commands were operating properly the fault was attributed instead to a mechanically stuck secondary air injection combination valve despite this revised diagnosis, the issue has remained unresolved. As of 2026, a dealership evaluation has now attributed the same fault condition to a potential failure within the cylinder head assembly, indicating a significantly more serious underlying condition. Safety concern: this issue involves the emissions and engine air management system and has resulted persistent check engine light repeated failure of emissions-related components conflicting and escalating repair diagnoses across multiple qualified service providers I am requesting that the national highway traffic safety administration review this issue for potential investigation into a systemic defect. Information redacted pursuant to the freedom of information act (foia), 5 u. S. C. 552(b)(6).
Oil pressure sensor fails. Causing high oil pressure. Causing the valve cover to be destroyed and the oil pan to leak. Draining the car oil.
Bought car from dealer. Vw manhattan. 42000miles. 8 months later at 53000 miles. Engine problems. Went to vw service. Head gasket. Lemon car. Warranty till 50000 miles. Cost? 4800$ worse car possible.
The contact owns a 2020 Volkswagen Passat. The contact stated while driving at various speeds, the vehicle made abnormal sounds. The contact stated that the vehicle started independently, and the driver assist function engaged independently. Additionally, the contact stated that the vehicle was swerving unintendedly and would vibrate while driving. The vehicle was taken to the dealer several times; however, the dealer informed the contact that they could not duplicate the failure. The dealer later replaced the brake rotors; however, the failure persisted. The electronic power control (epc), the adaptive cruise control and low oil pressure warning lights were illuminated. Additionally, the message "front assist error" was displayed. The vehicle was taken to the dealer, where it was diagnosed that the brake caliper was fractured. The vehicle was not repaired. The contact stated that the dealer had previously replaced the thermostat as the message "coolant error" was displayed on the instrument panel. The manufacturer was notified of the failure, but no assistance was provided. The failure mileage was approximately 7,000.
Park assist not availble. Loss of engine power on left or right turn.