Service

Technical Information

17/18

ENU

1001

1

Complaint - Engine Knock During Acceleration: Checking Engine for Carbon Deposits
(17/18)
Revision:

This bulletin replaces bulletin Group 1, #17/18, dated February 13, 2018. Under Invoicing, Damage Type
“3015 – Dirty” was changed to “1117 – Misfiring, Jerking

Model Year:

As of 2010

Model Line:

Cayenne (92A)
Panamera (970/971)
Macan (95B)

Subject:

Intake valves and intake ports

Information:

Carboned-up valves in the engine can be reworked and cleaned using cleaning equipment.
If there is a complaint about knocking combustion, e.g. during acceleration at high load, the
condition of the intake valves and ports must be checked before doing any other work.
If the check shows that the intake valves and intake ports have carbon deposits and are dirty, they
must be cleaned using the VAS 294 011 - cleaning unit.
There should be no need to replace the components.

Date of
Introduction:

The VAS 294 011 - cleaning unit can be ordered immediately for dealers.

Remedial
Action:

The VAS 294 011 - cleaning unit is used for cleaning carboned-up intake valves and intake ports.
Compressed air is used to spray a special granulate mixture into the intake port, where it loosens and
removes carbon build-up.
The dirty granulate is extracted during spraying using an industrial vacuum cleaner.
Instructions for use can be found in the operating instructions of the cleaning unit:
•
•

Access the intake valves and ports via the intake-air distributor.
When working on the intake valves and ports using the cleaning unit, make sure that the
intake valves into the respective combustion chamber are closed  ignition TDC.

Tools:

VAS 294 011 - Cleaning unit (This is a recommended tool for dealerships to purchase, but can also be
rented.)

Invoicing:

For invoicing and documentation using PQIS, enter the following coding:

Location (FES5)

10010

Engine

Damage type (SA4)

1117

Misfiring, jerking

AfterSales

July 2, 2019
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1

Service
1001

ENU

Technical Information

17/18

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.

©2019 Porsche Cars North America, Inc.

July 2, 2019
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AfterSales