Fiat 1998 Marea Weekend, Service Manual

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Engine
Marea-Marea
Weekend©^
Fuel system 1998 range
10.
THROTTLE BODY (46 SXF 2)
The throttle body is responsible for metering the quantity of air supplied to the engine (and thus control-
ling engine power output) according to accelerator position determined by the driver.
The throttle body is fastened to the intake manifold by four screws. The throttle is opened by a linkage
with configuration designed to open the throttle by a small amount when the pedal is hardly pressed
(provided pedal travel remains the same) and open it by large amounts when the pedal is pressed down
further.
With the pedal fully released (engine in over-run or idling), the additional air required is supplied by an
engine idle adjustment solenoid. Under these conditions, the throttle opening lever comes into contact
with an anti-bind screw, which prevents the throttle becoming locked in closed position.
To prevent the build-up of ice around the throttle and the hole leading to the PCV valve, the throttle
body is heated by directing a small amount of coolant from the engine thermostat around a chamber in-
side the case.
The throttle position sensor and engine idle speed actuator are also fitted on the butterfly valve case.
1. Attachment for engine coolant delivery hose
2. Attachment for engine coolant return hose
3. Engine idle speed actuator
4. Throttle position sensor
5. Throttle valve
6. Throttle linkage
7. Throttle valve adjustment and antibind screw (do not touch)
32 Publication no. 506.763/09
The anti-bind screw is
set by flushing in the
factory and should nev-
er be tampered with.
P4F32IJ01