Management Of The Injection - Fiat Bravo Service Manual

E n g i n e
Fuel system
10.
In particular, the signal is composed as follows.
There are sixty teeth on the flywheel, t w o of w h i c h have been removed to create discontinuity: the angle
between the t w o consecutive teeth is therefore 6°:
The synchronism point is recognized at the end of the first tooth following the t w o missing teeth: the fly-
wheel is fitted so that as the engine passes this tooth cylinders 1 and 4 are 17 teeth before TDC.
1. Engine rpm and TDC sensor
2. Gap
3. Flywheel 60-2 teeth
M A N A G E M E N T O F T H E I N J E C T I O N
The injection management strategies are designed to provide the engine w i t h the. correct quantity of fuel
at the desired moment according to the engine operating conditions.
The management of the injection basically consists of calculating the injection time, determining the i n -
jection phase and then the implementation by operating the injector.
The "basic" injection time is calculated by means of mathematical interpolation of the speed-load map:
the figures contained in the map, w h i c h have been obtained experimentally, also depend on the charac-
teristics of the injector.
The " f i n a l " injection time "is determined by means of a calculation algorhythm in w h i c h the "basic" i n -
jection time is corrected by a series of coefficients w h i c h take into account the different engine operat-
ing conditions w h i c h are highlighted by the various system sensors.
6
4. Signal corresponding to two missing teeth
5. Flywheel signal (engine speed sensor)
lev
98 range
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