2053424.2

Technical Service Bulletin
Topic
Market area
Brand
Transaction No.
Level
Status
Release date
Bentayga W12 - Misfire after start up in cold conditions
Bentley: worldwide (2WBE),Hongkong-Macau (5HK)
Bentley
2053424/2
GH
Released for publishing
May 17, 2019
New customer code
Object of complaint
engine -> engine operation -> engine running
engine -> engine operation -> engine running
engine -> engine operation
engine -> engine operation
Complaint type
Position
functionality -> misfire
functionality -> irregular
functionality
noises, vibrations
Vehicle data
Bentayga W12
Sales types
Type
4V14*
4V14*
4V14*
4V14*
MY
2017
2018
2019
2020
Brand Designation Engine code Gearbox code
E
*
*
E
*
*
E
*
*
E
*
*
Documents
Document name
master.xml
Final drive code
*
*
*
*
Technical Service Bulletin
Bentayga W12 - Misfire after start up in cold conditions
Transaction No.: 2053424/2
Release date: May 17, 2019
Condition
Misfire after start up in cold conditions (below 0° Celsius)
The misfire can cause a start/stop malfunction initially followed by an engine warning lamp illuminated within the Driver Information panel (DIP)
Technical Background
Should the retailer receive a complaint which matches the above symptoms, follow all instructions within the Measure section of this TPI
Production Solution
Not applicable
Service
Misfires must be evident during an initial cold start (below 0° Celsius) Do Not perform any other methods of Diagnosis unless
instructed - Refer to the onward instructions if the symptoms and criteria are as described
1) Carry out a Guided Fault Finding (GFF) sweep of all control modules IMPORTANT: Save and attach the diagnostic log to the open DISS query
NOTE: The retailer should include as much information as possible within the DISS query relating to customer driving style/patterns regarding when
the issue occurs for example - When the car is parked outside overnight the engine misfires on start up in temperatures below 0° Celsius
2) Clear all DTC’s and attempt to replicate the customer concern in exactly the same conditions and temperature as the customer experienced the
issue
IMPORTANT: Should the misfires still be evident Product support should advise the retailer to carry out the following onward steps
3) Carry out a second (GFF) sweep of all control modules – IMPORTANT: Save the diagnostic log to the open DISS query
IMPORTANT: Prior to starting any work on the fuel system observe the following:
Refer to Repair manual Rep.Gr 20 Fuel system - safety precautions and Repair manual Rep.Gr 20 Fuel system - safety precautions Fuel system - rules
for cleanliness
4) Refer to Elsa pro Rep.Gr 20 Draining fuel tank - Take a 4 litre fuel sample directly from the tank ensuring the Fuel extraction unit VAS 5190A is
empty and clean prior to starting the fuel extraction procedure IMPORTANT: Do not drain any fuel into the VAS 5190A unless it is empty and clean
as the fuel must be transferred from the VAS 5190A unit into a brand new sealable fuel container (retailer should source the container locally)
NOTE: A brand new container must be used to eliminate cross contamination, the fuel sample should stay in the container until otherwise advised via
DISS or by a regional sampling company, the sampling company may request the fuel sample or send another container to the retailer in which the
fuel should be transferred and dispatched to the required location
5) Visually inspect all spark plugs and attach photographs of each spark plug NOTE: Ensure the photographs are clearly marked regarding which
cylinder the spark plug was removed from
6) Perform a compression and leak down test on all 12 cylinders as per TPI 2051187/1 (Attach the results within the DISS query)
7) Remove the low pressure injectors - Refer to Repair manual Rep.Gr 24 attach photographs of each low pressure injector tip NOTE: Ensure the
photographs are clearly marked regarding the cylinder position (1 through to 12)
8) Using a Boroscope, Attach photographs of the HIGH PRESSURE injectors Tips NOTE: Ensure the photographs are clearly marked regarding
cylinder position (1 through to 12)
9) Retailer to ensure all requested information is provided on the open DISS query
Required Parts and Tools
Retailer should not replace any parts unless instructed via the open DISS query