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P2421 on the 2026 Porsche Cayenne

The bulletins listed name this code in NHTSA's summary, or are about the same components. A bulletin or a recall listed here may apply to the model year. None of it is a diagnosis.

Nobody has written a description of this code yet.

Bulletins for this model year that name P2421
No. 2521.12025-10-08. Service bulletin. Instructions on advanced technical information for the Cayenne. DME P242100 – Fuel Tank Isolation Valve for Tank Ventilation System Stuck Open
No. 25212025-09-09. Service bulletin. Instructions on advanced technical information for the Cayenne DME P242100 – Fuel Tank Isolation Valve for Tank Ventilation System Stuck Open. Models affected are 9YAAV1, 9YABN1, 9YACT1, 9YBAV1, 9YBBN1, 9YBCT1

2 on file from NHTSA, as of 2026-10-19. See them in the bulletin list. A bulletin lists model years: read the document for which vehicles it concerns.