Subaru 2002 Impreza Service Manual page 48

CONTROL SYSTEM
Fuel Injection (Fuel System)
Ignition control after start of engine
Between the 97" and 65" crank angle signal, the ECM measures the engine speed, and by using
this data it decides the dwell set timing and ignition timing according to the engine condition.
#4 #1 #3 #2 #4
(1)
I
I I I I
97" 65" 10" 97" 65" 10" 97" 65" 10" 97" 65" 10"
(2)
I 1 I I I
I I I
1 I I I
20"
27.5"
501
[
20" 20" 50"
20"
(6)
I
#4
i
#1
I
#3
I
#2
I
(1) Cylinder number
(2) Crank angle pulse (BTDC)
(3) Cam angle pulse (ATDC)
(4) Ignition timing at starting
B2H041 O D
(5) Ignition timing at normal condition
(6) Burning cylinder
(7) Dwellset
(8) Ignite
FU-32