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Spark Plug - Recommeded Usage

90porsche06 October 5, 1990
Subject: Spark Plug Usage
Model Group

944 S2 2

Part Identifier Number

2870 9006
ATTENTION: Service Manager/Service Technician

Models Affected: 944 S2 model years 1989, 1990 and 1991

Concern: 944 S2 engines can be equipped with either WR 5 DC or WR 7 DC spark plugs. In general, vehicles delivered after August 1990 will be equipped with WR 7 DC plugs. The WR 7 DC plug is preferred for use in vehicles which experience prolonged storage or frequent engine starts followed by short running times since this plug reaches a self cleaning temperature more quickly than the WR 5 DC plug.

The WR 5 DC plug and the WR 7 DC plug can be used interchangeably but they must not be mixed in an engine. The WR 7 DC may be replaced by the WR 5 DC anytime (for example at the 30,000 mile maintenance).

Parts Information: WR 5 DC - Part Number 999 170 179 90 WR 7 DC - Part Number 999 170 158 90
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