Porsche 928 Workshop Manual page 620

928 S4
928 GT Fuel System I Electronic Control
28
To display a secondary image at the oscillo-
scope, the engine tester must be switched to 4
cylinders, since the car's ignition system is
divided into 2 separate ignition circuits.
Firing order:1 -3-7-28-5-4-8
Jl-lk-.I, I--
Ignition circuit I: 1 7
6 4 1
High-tension distributor on exhaust camshaft
for cylinders 14:
Cylinders:
I-7-6-4
Ignition circuit II:
High-tension distributor on exhaust camshaft
for cylinders 5-8:
5-6-34
The high-tension power supply for ignition cir-
cuit I comes from the coil installed at the front
right, the high-tension power supply for igni-
tion circuit II comes from the coil installed at
the front left.
a) Connecting the engine tester
Connect and adjust the engine tester in accord-
ance with the manufacturer's instructions (note
that the 4-cylinder measuring range must be
selected).
To display the ignition pattern for ignition cir-
cuit I (right side), connect the tester to the igni-
tion lead for cylinder 1 and the front right coil.
EZK-Diagnosis/Troubleshooting
Printed In Germany - XXV, 1990
D28-13