NHTSA ID Number: 10249919
Manufacturer Communication Number: No. 166-21-2
TSB/Document Date: 2024-02-08
Summary
Technical information for Oil Leakage on Cylinder Head Cover: Insert Micro-Self-Locking Screw
Service
Technical Information
166/21 ENU
1582
1
Oil Leakage on Cylinder Head Cover: Insert Micro-Self-Locking Screw (166/21)
Revision:
This bulletin replaces bulletin Group 1 166/21, dated December 10, 2021.
Model Year:
As of 2017 up to 2024
Model Lines:
Panamera (971)
Equipment:
8-cylinder Otto engine (engine type: CVD)
Concerns:
Oil leakage around the cylinder head cover
Cause:
The customer complains about an oil leakage in the engine compartment. “Oil sweating” or drops of oil
forming in the cylinder head cover area is detected in the workshop.
Information
The measure described here relates to a potential oil leak at the screws shown on the cylinder head
cover. If the oil leak occurs at another location, the oil leak must be found and remedied. This Technical
Information (TI) does not apply in this case.
Example of an oil leakage
Action required: Clean the affected area thoroughly and replace the affected screws and adjacent screws with micro-selflocking screws.
AfterSales
Jan 30, 2024
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1
Service
1582
Technical Information
ENU 166/21
Overview of potentially affected screw points, bank 1
Overview of potentially affected screw points, bank 2
Jan 30, 2024
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Service
Technical Information
166/21 ENU
1582
1
Information
To clearly identify an oil leak and avoid unnecessary repairs, always proceed as follows:
•
Document the original complaint condition with meaningful photos
•
Attach documentation to PCSS line.
•
Clean the engine thoroughly
•
Where applicable, spray large areas of the engine with leak search spray (“SpotCheck”) around the
suspected leakage points
•
Perform a test drive
•
Check the engine for leaks and find the leak
•
Produce photo documentation of the leakage point located
•
Attach documentation to PCSS line.
Information
Definition and procedure for oil leaks:
•
Oil sweating: Oil is visible; however, the amount of oil emerging is does not form drops of oil. There
are no traces of oil on adjacent components. No further action is required in this case.
•
Drops of oil: A significant amount of oil is clearly visible; the emerging oil forms drops of oil. There
are also traces of oil on adjacent components. In this case, the leak must be located and remedied.
Parts required if necessary
Information
The number of screws required depends on the respective leakage point on the cylinder head cover.
Parts Info:
Required parts:
Screw No.
Part No.
Designation
– Location
Number
1
N 10451409
Internal hexagon round countersunk
screw, self-locking, M6 x 16
– Cylinder head
As required
or
2
N 10599501
Countersunk screw M5 x 20
– Cylinder head
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As required
Jan 30, 2024
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Technical Information
ENU 166/21
1582
or
3
Internal hexagon round oval-head
screw
– Cylinder head
PAF101243
As required
Preparatory work
Work Procedure: 1
Remove fuel collection pipe.
For instructions, see:
Workshop Manual '243019 Removing and installing fuel collection pipe (V8 Turbo)'
Replace affected and adjacent screws
Information
The surrounding screws around the leakage must in
principle also be replaced with microencapsulated
self-locking screws analogous to the example shown in the
graphic Example of "adjacent screws".
Work Procedure: 1
Unscrew the affected and adjacent screws.
2
Clean the affected area thoroughly.
3
Blow out bores using compressed air.
4
Screw in and tighten new micro-self-locking screws at
the relevant position.
Check the following while doing this:
•
•
•
Example of "adjacent screws"
Screws for fuel collection pipe (item 1) Initial tightening 7 Nm (5.2 ftlb.) Final tightening
10 Nm (7.4 ftlb.) Also observe screw sequence. For instructions, see: Workshop Manual
'243019 Removing and installing fuel collection pipe (V8 biturbo)'
Screw for solenoid hydraulic valve VHS (item 2) Tightening torque 5 Nm (3.7 ftlb.)
Screws for pressure converter holder (item 3) Tightening torque 10 Nm (7.4 ftlb.)
Follow-up actions
Work Procedure: 1
Jan 30, 2024
Page 4 of 5
Install fuel collection pipe.
For instructions, see:
Workshop Manual '243019 Removing and installing fuel collection pipe (V8 Turbo)'
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Service
Technical Information
166/21 ENU
1582
1
Labor position and PCSS encryption
Labor position:
I No.
APOS
Labor operation
15824931
Subsequent work on cylinder head
15824932
Subsequent work on cylinder head
PCSS encryption:
Location (FES5)
15820
Cylinder head cover
Damage type (SA4)
5043
Oil loss
References:
Workshop Manual '243019 Removing and installing fuel collection pipe (V8 Turbo)'
Important Notice: Technical Bulletins issued by Porsche
Cars North America, Inc. are intended only for use by professional automotive technicians who have attended Porsche
service training
courses. They are written to inform those technicians of conditions that may occur on some Porsche
vehicles, or to provide information that could assist in the proper servicing of a vehicle. Porsche
special
tools may be necessary in order to perform certain operations identified in these bulletins. Use of tools and procedures other than those Porsche
recommends in these bulletins may be detrimental to the
safe operation of your vehicle, and may endanger the people working on it. Properly trained Porsche
technicians have the equipment, tools, safety instructions, and know-how to do the job properly and
safely. Part numbers listed in these bulletins are for reference only. The work procedures updated electronically in the Porsche
PIWIS diagnostic and testing device take precedence and, in the event of a
discrepancy, the work procedures in the PIWIS Tester are the ones that must be followed.
© 2024 Porsche
Cars North America, Inc.
AfterSales
Jan 30, 2024
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TSB/Document ID: No. 166-21-2
Replacement Service Bulletin Number:
MFR Communication Date: 2024-01-30
MFR Internal Campaign ID/Software Version:
Communication Type: Service Bulletin/Repair Instructions
NHTSA Components: EQUIPMENT
MFR Component System:
MFR Component Subsystem:
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