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Service bulletin 2028794/8

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

The communication, as NHTSA indexes it (as of 2026-10-19)
TypeService bulletin
NHTSA id11015981
Published by NHTSA2025-03-27
Manufacturer's number2028794/8
Manufacturer's date2025-03-04
NHTSA componentENGINE

NHTSA's summary

Engine coolant mixture - Restrictions on use of desalinated water. Technical Background: An important factor of influencing the cooling system efficiency is the water used in the mixture Due to the different ingredients and characteristics existing in each country or even region, Bentley has decided to define the quality of water for cooling systems Demineralised water according to standard VDE 0510 meets all requirements and can be purchased worldwide Therefore undiluted coolant should be mixed in the correct ratio using demineralised water as detailed in Elsa Pro coolant specification, this will detail the ratio and type of coolant to use The use of desalinated water in the engine cooling system is specifically prohibited

The document

The document is the manufacturer's. This site does not hold it. NHTSA files a document at one of these two addresses; we have not asked NHTSA which.

Components

Engine

Vehicles listed
BENTLEY BENTAYGA2017, 2018, 2019, 2020, 2021, 2022, 2023
BENTLEY BENTAYGA2025
BENTLEY BENTAYGA HYBRID2019, 2020, 2021, 2022, 2023, 2024, 2025 (the catalog's model; the bulletin names a series or trim of it)
BENTLEY CONTINENTAL GT2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020, 2021, 2022, 2023, 2024, 2025 (the catalog's model; the bulletin names a series or trim of it)
BENTLEY CONTINENTAL GT CABRIO2007, 2008, 2009, 2010, 2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020, 2021, 2022, 2023, 2024, 2025 (the catalog's model; the bulletin names a series or trim of it)
BENTLEY FLYING SPUR2006 to 2013
BENTLEY FLYING SPUR2014, 2015, 2016, 2017, 2018, 2019, 2020, 2021, 2022, 2023, 2024, 2025
BENTLEY FLYING SPUR HYBRID2022, 2023, 2024 (the catalog's model; the bulletin names a series or trim of it)
BENTLEY MULSANNE2009 to 2010
BENTLEY MULSANNE2011, 2012, 2013, 2014, 2015, 2016, 2017, 2018, 2019
BENTLEY redundant BENTAYGA2024
BENTLEY redundant FLYING SPUR HYBRID2025

Listing a model year does not mean every vehicle of it is concerned: the document says which.

Other bulletins for the same vehicles and component
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2081085/22026-08-06. Service bulletin. V8 Engine - Ticking Noise, Misfiring and Possible Low Oil Pressure Indications. Customer statement: The customer may report an audible ticking noise from the top of the engine, low oil pressure warnings / MIL on the Driver Information Panel, and/or misfiring during engine operation
2051187/132026-08-05. Service bulletin. Poor Engine Running Complaints (Misfires) Petrol Engines Only. Customer statement / workshop findings: • Poor engine running • Reduced power • Engine warning lamp illuminated • Symptom related DTC’s evident within the applicable engine control unit(s)
2068273/62026-08-03. Service bulletin. Multiple random misfires evident during PDI.
2065664/62026-08-01. Service bulletin. Bentayga V8 Kovomo - Engine MIL light on - DTC “O2 Sensor Signals Swapped Bank 1 Sensor 2/ Bank 2 Sensor 2. Customer statement / workshop findings: DTC P004100: “O2 Sensor Signals Swapped Bank 1 Sensor 2/ Bank 2 Sensor 2 is evident within address 0001 (Engine control unit) and MIL light active after attempting to conduct a readiness test
2081236/22026-08-01. Service bulletin. Loss of Cabin Heat During Engine Operation | Bentayga - V8. Customer Statement: Customers may report that the air conditioning system blows only cold air when the engine is running. Warm air is only available after switching off the engine. The concern is commonly reported after engine removal or recent repair work.
2071190/42026-08-01. Service bulletin. HVAC failing to cool | DTC B16A1F0 in diagnostic address 00C5 | Bentayga Series (Hybrid).