Ford Festiva. Instruction - part 49

located under the center of the instrument panel, between the panel and the floor.

Fig. 4: Electric Fuel Pump System Schematic

Courtesy of FORD MOTOR CO.

FUEL PRESSURE REGULATOR

The fuel pressure regulator is located at the fuel return end of the fuel rail and maintains fuel pressure within the fuel rail at a constant 36.3 psi
(2.54 kg/cm

) higher than intake manifold pressure.

FUEL PRESSURE REGULATOR CONTROL SOLENOID (PRC) (CAPRI)

This device closes the vacuum supply to the fuel pressure regulator on hot starts, thus increasing fuel pressure within the fuel rail and
preventing fuel percolation which could cause hard starts during hot conditions. The PRC is located on the cowl panel, next to the canister
purge solenoid.

FUEL PUMP SHUT-OFF (INERTIA) SWITCH

The fuel pump shut-off switch is connected in series with the fuel pump and prevents fuel pump operation in the event of major collision or
vehicle rollover. A reset button is provided to reset the switch after it has been triggered. See

Fig. 5

Fig. 5: Locating Inertia Switch Reset Button

Courtesy of FORD MOTOR CO.

FUEL CONTROL SYSTEM

ELECTRONIC FUEL INJECTION (EFI)

The ECA receives a signal from the CPS (Festiva) or CID (Capri) for basic fuel injector timing. Signals to the ECA from other sensors and
switches affect injector on-time. The amount of fuel injected is determined by the duration of the electronic pulse sent to the fuel injector from
the ECA.

Between idle and 5000 RPM, fuel is supplied by providing one injection per crankshaft rotation (2 injections per cycle) to all cylinders. There
is one injection per 2 crankshaft rotations when engine speed exceeds 5000 RPM. When engine speed exceeds 6400 RPM, fuel injectors are
shut off to prevent engine damage.

IDLE SPEED

While the engine is cold, the Idle Speed Control By-Pass Air (ISC-BPA) Valve increases idle speed to warm the engine quickly. At engine
temperatures less than 140°F (60°C), the valve is open. As the engine warms, the valve begins to close. The valve is fully closed at engine
temperatures higher than 140°F (60°C). Idle speed is also affected by various switches, sensors and load on the engine.

ELECTRONIC IGNITION SYSTEM

CAPRI

A pick-up coil within the distributor sends a signal to a Distributor-Mounted Ignition Module With Vacuum Advance (DMIVA) within the
distributor. The DMIVA then sends a signal which fires the coil. When the coil fires, the distributor directs high voltage current to the spark
plugs. The DMIVA system operates independently of the ECA.

FESTIVA

A pick-up coil within the distributor sends a signal to a transistorized ignition module on the coil bracket. A timing signal also goes from the
ECA to the ignition module. The ignition module then sends a signal which fires the coil. When the coil fires, the distributor directs high
voltage current to the spark plugs.

IGNITION TIMING CONTROL SYSTEM

CAPRI

Spark timing is controlled by vacuum and centrifugal advance mechanisms and by a signal from the ECA. The ECA does not affect ignition
timing on turbo models. On turbo models, a knock sensor and control unit retard ignition timing when knock occurs.

FESTIVA

The ECA generates a spark timing signal from data received from the BP, CPS and VAF. This signal goes to the ignition module. The ignition
module then sends a signal to fire the coil.

HIGH ALTITUDE SPARK ADVANCE CORRECTION

A barometric pressure sensor is incorporated into the ECA on Festiva and is a separate component on Capri. At high altitudes, the ECA sends
a signal to the ignition module to advance ignition timing. This feature is not used on turbo models.

KNOCK SENSOR (CAPRI)

A Knock Sensor (KS) generates a signal when knock occurs. A control unit processes this signal and then sends it to the ignition module to
retard spark timing. The KS is located in the engine block, near the oil pressure switch. This device is only used on 1.6L turbo engines.

KNOCK CONTROL UNIT (CAPRI)

The Knock Control Unit filters normal engine vibration signals from the KS, then sends a signal to the ignition module to retard spark timing.
This unit, used only on 1.6L turbo engines, is located on right side of engine compartment.

EMISSION SYSTEMS

DECELERATION SYSTEM (DASHPOT)

The deceleration control system closes the throttle plate gradually during deceleration. The dashpot prevents engine stalling on deceleration
and provides a smooth transition from deceleration to sudden acceleration.

EVAPORATIVE SYSTEM

CARBON CANISTER

The carbon canister stores vapors from the fuel tank until they are purged and burned in the engine. On Festiva, carbon canister is
located under the brake booster. On Capri, carbon canister is located on the right side of the engine compartment near the cowl panel.

CANISTER PURGE SOLENOID

This component is connected between the carbon canister and intake manifold. When the ECA sends a signal to the solenoid to open,
fuel vapors in the carbon canister are drawn into the engine.

CANISTER PURGE VALVE

This valve opens to purge vapors from the carbon canister into the engine intake system. The valve is part of the canister purge solenoid.

ROLLOVER VENT VALVE

This valve, located in front of the fuel tank, blocks the vapor line in case of vehicle rollover.

CATALYTIC CONVERTER

The catalytic converter is in the exhaust system, between the exhaust manifold and the muffler. It converts certain pollutants in the exhaust

gases into harmless substances.

PCV VALVE

The Positive Crankcase Ventilation (PCV) valve, located in the valve cover, controls the flow of blow-by gas from the crankcase to the intake
manifold.

SELF-DIAGNOSTIC SYSTEM

The ECA monitors its inputs and outputs. When it detects a malfunction, it sets a code in the ECA and sends a signal to the CHECK ENGINE
warning light. The light remains on until the malfunction is repaired. Trouble codes may be accessed at the Self-Test Output (STO) and Self-
Test Input (STI) connectors, near the battery.

If a sensor fails, the ECA will use a substitute value in its calculations to permit continued engine operation. In this condition, the vehicle will
run, but driveability may be poor. Intermittent failures may result in the CHECK ENGINE warning light flickering or going out after the fault
goes away. The corresponding trouble code, however, will be stored in the ECA. If fault does not recur, the related code will be erased from
ECA memory.

CHECK ENGINE LIGHT

Hard failures cause the CHECK ENGINE warning light to come on and remain on until the malfunction is repaired. If the warning light comes
on and stays on during vehicle operation, determine and correct the cause of the malfunction.

NOTE:

For additional information and operating procedures for the self-diagnostic system, refer to TESTS
W/CODES article in the ENGINE PERFORMANCE Section.

Article GUID: A00022697

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