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ENGINE 1.3L QUADRAJET (90PS)
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3A.1.8.4 DIESEL FUEL INJECTION SYSTEM
3.1.8.4.1 FUNCTION
The Magneti Marelli MJD 6F3 Common Rail system
is a high pressure electronic injection circuit for fast,
direct injection diesel engines.
Its main features are :
Q
Availability of high injection pressures (1400 bar)
for the 75 CV version;
Q
Availability of high injection pressures (1600 bar)
for the 90 CV version;
Q
Possibility of modulating these pressures between
150 bar and the maximum operating value of 1400
bar for the 75 CV version and 1600 bar for the 90
CV version irrespective of the rotation speed and
the engine load;
Q
Ability to work at high engine rpms (up to 5000
rpm in full load conditions);
Q
Injection control precision (injection advance and
duration);
Q
Reduction in fuel consumption;
Q
Reduction in emissions.
Main system functions are essentially as follows:
Q
Engine coolant temperature control;
Q
Control of amount of fuel injected;
Q
Idle speed check;
Q
Fuel cut-off during over-run;
Q
Cylinder balance check when idling;
Q
Control of anti-judder function
Q
Exhaust fumes control during acceleration;
Q
Exhaust gas recirculation control (E.G.R.);
Q
Maximum torque limit control;
Q
Maximum speed limit control;
Q
Control of heater plugs;
Q
Control of climate control system activation (where
fitted);
Q
Auxiliary fuel pump check;
Q
Cylinder position check for timing;
Q
Main and multiple injection advance check;
Q
Injection pressure closed cycle check;
Q
Electrical balance check;
Q
IMA injector calibration;
Q
Fuel pressure control;
Q
Lambda sensor control;
Q
Control of variable geometry compressor (90 CV
version);
Q
Engine oil life check.