Porsche 928 Workshop Manual page 516

2f?
Ignirion SyrLem
!I 28
II *
I~
a
CtlECKING I~~N,l',ON TIMING - Fro,,, I!!80 Models
Requirements:
Ignition riming adjustment is correct.
1. Check centrifugal advance (see rable).
2. Check vacu"m unit (see table)
Vacuum connerrions
1 - Advance
2 - Retard
Idle speed vacuum available at connection 2 can be
used to check ignition advance.
This requires connecting the vacuum hose from
retard unit to the advance unit.
After completion of tests reconnect vacuum
hoses.
If specified testing values can ' I be reached. re-
a
move disrributor for inspection on a resr bench.
a
28 - 24 Checking Ignition Timing
Printed in Germany