Fiat 1998 Marea Weekend, Service Manual

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Engine
Marea-Marea Weekend^**
Fuel system
1998 range
10.
I N J E C T O R S (IWP 064)
The twin-jet top-feed injectors (spray is inclined in relation to the injector centre-line) are specific for
four valve per cylinder engines. They allow the jets to be directed toward the two intake valves.
Fuel jets at a differential pressure of 3 bars leave the injector and are immediately nebulised to form two
propogation cones.
The injector control system is «timed, sequential)) type, i.e. the four injectors are controlled in accordance
with the engine cylinder intake sequence. Fuel delivery for each cylinder may begin during the expan-
sion stage and last through to the a point when the intake stage has already begun.
The injectors are held in place by the fuel manifold, which presses them into their seats on the intake
ducts. They are also anchored to the fuel manifold by safety clips. Two viton rings (1) and (2) form a
seal on the intake duct and fuel manifold.
Fuel is supplied from the top part (3) of the injector. Th case contains winding (4) connected to termi-
nals (5) of electrical connector (6).
NOTE When removing-refitting, do not apply stresses higher than 120 N to injection connector (6) or it may be
damaged..
Ill
W\
mi \\\\
inn \\\\\
mn \\\w
Wiring connector Checking resistance
NOTE The numbers in boxes indicate ECU pin
no. in order of cylinder number.
The injector resistance may be measured by
disconnecting connector and connecting an
ohmmeter as shown in the figure.
Resistance: 13.7 - 15.2 ohm at 20 C
44
Publication no. 506.763/09