911 Turbo F6-3299cc 3.3L SOHC Turbo (1992)
Spark Plug: Technical Service Bulletins
Spark Plug - Usage
September 24, 1991
Model
Group
911 turbo
2
1991-92
Part Identifier
Number
2870
9103
Subject:
Spark Plug Usage
ATTENTION: Service Manager/Service Technician
This bulletin replaces Technical Bulletin Group 2, Number 9103, dated 9-6-91.
Models Affected:
911 turbo 1991-92
Concern:
1991-92 911 turbo engines can be equipped with either WR 4 DPO or WR 6 DPO spark plugs. The WR 6 DPO spark
plugs started in production July 1991. The WR 6 DPO spark plug is preferred for cars used on frequent short trips or cars
that are infrequently run since this plug reaches a self-cleaning temperature more quickly than the WR 4 DPO.
The WR 4 DPO and the WR 6 DPO can be used interchangeably, but they must not be mixed on an engine.
Parts Information:
WR 4 DPO - Part Number 999 170 186 90
WR 6 DPO - Part Number 999 170 190 90