Saab 9000 - Page 20

Technical Description 17
Saab Trionic system overview (contd.)
The Saab Trionic is an engine management syste!'Tl
which controls ignition timing, fuel injection and boost
pressure from one and the same electronic control
module.
The Saab Trionic system was introduced in 1993 on
Saab 9000 models fitted with the B234L engin~.
Model y~ar 1996 and later cars for the USA market
are equipped with the On-Board Diagnostic II sys-
tem, entailing the following component changes:
• Oxygen sensor also after the three-way catalytic
converter
(rear heated oxygen sensor)
• A number of sensors are fitted with different con-
nectors or gold-plated pins.
Saab 9000
Service Manual
2:7 Engine Management System
Trlonlc 080
II
M 1996-
The Saab Trionic ignition system consists of an igni-
tion discharge module with four ignition coils, one for
each spark plug. The ignition system is of capacitive
type. Since ,he spark plugs are used as sensors to
detect combustion and knocking, neither camshaft
position sensors nor knock sensors are needed. The
system also supports efficient detection of misfiring,
which is an On-Board Diagnostic II system require-
ment.
Fuel injection is sequential and regulated by the in-
take manifold pressure. Boost pressure control is ef-
fected by means of a solenoid valve connected to the
turbo unit's wastegate. The Saab Trionic engine
management system designed by Saab has tremen-
dous development potential. ·
Saab 9000
I