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Ignition System - Malfunctioning

87porsche05

Subject: Check Ignition System

After Engine Repairs
Model

928 S4
Group

2
Part Identifier

2800
Number

8717
December 11, 1987
An ignition circuit which is not functioning properly causes excessive temperatures at the catalytic converter and therefore influences its functions.

After performing any repairs on the engine, in the engine compartment, or near the central electric board, always check the following ignition wiring connections for tightness and good contact.

Caution: Turn off the ignition when working on the ignition system. (dangerous high voltage)
Ignition coil left: Terminal 1 and 15, High tension ignition lead term. 4
Ignition coil right: Terminal 1 and 15, High tension ignition lead term. 4
Ignition Distributor left and right: Distributor cap and ignition wire plugs
Spark Plugs: Spark plug connectors and high tension wires
Ignition Final Stages: Plug connectors, ground connection and mounting bolts.
Central Electric: Plug Q, EZK control unit plug and plug connection for ignition final stages (green and white wire).