Ford Festiva. Instruction - part 41

Connect BOB. Remove dust cover from BP sensor, located on passenger side cowl. Turn ignition on. Connect vacuum pump to BP sensor.
Measure voltage between pins BP and SIGRTN on BOB while applying vacuum to BP sensor. See

BAROMETRIC PRESSURE SENSOR

OUTPUT VOLTAGE

. Replace BP sensor if voltage is not as specified.

BAROMETRIC PRESSURE SENSOR OUTPUT VOLTAGE

BRAKE ON-OFF (BOO) SWITCH

Unplug connector from BOO switch at brake pedal. Connect ohmmeter to switch terminals. With pedal released, ohmmeter should indicate no
continuity. Ohmmeter should indicate continuity with pedal depressed.

CLUTCH ENGAGE SWITCH (CES)

Unplug connector from CES switch at clutch pedal. Connect ohmmeter to switch terminals. With pedal released, ohmmeter should indicate
continuity. Ohmmeter should indicate no continuity with pedal depressed.

CRANKSHAFT POSITION SENSOR (CPS) (1.3L)

Unplug 3-wire connector from distributor. Measure resistance between CPS terminal on distributor (Yellow/Blue wire) and ground. Replace
CPS if resistance is not 210-250 ohms.

CYLINDER IDENTIFICATION (CID) SENSOR (1.6L)

Turn ignition off. Connect BOB, leaving ECA connected. Turn ignition on, but DO NOT start engine. Measure voltage at BOB pin No. 34
(Yellow wire). Volt- meter should indicate less than one volt or more than 10 volts. Start engine and run at idle. Voltmeter should indicate 3-
5 volts. Replace CID sensor if voltage is not as specified.

ENGINE COOLANT TEMPERATURE (ECT) SENSOR

1. Remove ECT sensor. ECT sensor is threaded into top of lower intake manifold on 1.3L, and on underside of intake manifold on 1.6L.

Place ECT sensor and thermometer into container of coolant.

2. Connect ohmmeter to coolant temperature sensor terminals. Cool or heat container. Note resistance at specified temperatures. See

ENGINE COOLANT TEMPERATURE SENSOR RESISTANCE

. Replace ECT sensor if resistance is not within specification.

ENGINE COOLANT TEMPERATURE SENSOR RESISTANCE

EXHAUST GAS OXYGEN (EGO) SENSOR

With engine at normal operating temperature, unplug connector from EGO in exhaust manifold. Measure voltage between EGO sensor
terminal and ground. Voltage should increase with increasing engine speed and decrease with decreasing engine speed. Voltage at idle should
fluctuate within a range of .2-.8 volt.

IDLE SWITCH (1.6L)

Unplug connector from throttle position sensor on throttle body. Connect ohmmeter to switch terminals IDL and ground (Green/Orange and
Blue/Yellow wires on mating connector). Resistance must be less than 5 ohms with throttle in idle position, and more than 10,000 ohms with
throttle pedal depressed.

KNOCK SENSOR (1.6L TURBO)

Disconnect vacuum hose at distributor. Connect timing light. Start engine and record ignition timing. Tap intake plenum with a plastic mallet.
Knock sensor is okay if timing retards. If timing does not retard, check associated circuitry and components. See

TIMING CONTROL

SYSTEMS

under IGNITION SYSTEM.

NEUTRAL GEAR SWITCH (M/T)

1. Unplug connector near transmission. Place transmission in Neutral. Resistance across switch should be infinite.
2. Place transmission in any other gear. Resistance across switch should be zero ohms. If necessary, replace switch.

Vacuum In. Hg.

(1)

Voltage

3.84

3.36

2.66

1.93

1.26

.58

(1)

Voltage may vary by plus or minus 15 percent.

Temperature °F (°C)

Ohms

-4 (-20)

14,600-17,800

68 (20)

2200-2700

104 (40)

1000-1300

140 (60)

500-650

176 (80)

290-350

NOTE:

A steady voltage higher than .55 volt indicates a continuously rich condition. A steady voltage lower
than .55 volt indicates a continuously lean condition.

POWER STEERING PRESSURE SWITCH

1. Start engine and run it at idle. Remove connector from switch. Connect ohmmeter to switch terminals. Turn steering wheel from side to

side while observing ohmmeter.

2. Replace power steering switch if continuity does not exist with front wheels turned, or if continuity exists with wheels straight ahead.

THROTTLE POSITION SENSOR (1.6L)

Unplug connector from sensor. Connect ohmmeter to sensor terminals TP and SIGRTN (Orange and Blue/Yellow wires on mating connector).
Measure resistance at each throttle opening specified in

THROTTLE POSITION SENSOR RESISTANCE

. Replace sensor if resistance is

not within specification.

THROTTLE POSITION SENSOR RESISTANCE

THROTTLE POSITION SWITCH (1.3L)

1. Ensure idle speed and ignition timing are adjusted to specification. Stop engine. Disconnect negative battery cable.

2. Unplug TPS connector at throttle body. Insert appropriate feeler gauge between throttle stop screw and stop lever. Check for continuity

between specified terminals on TPS connector. See ON-VEHICLE ADJUSTMENTS article and TPS CONTINUITY table.

TPS CONTINUITY

VANE AIRFLOW (VAF) METER

1. Check all wiring, harnesses, connectors and components for evidence of damage, overheating, shorting or looseness. If any defect exists,

repair as necessary.

2. Inspect vane airflow meter for damage and ensure measuring plate moves smoothly. Install BOB. Turn ignition on. Measure voltage

between BOB test pins VAF and ground on 1.3L, or between VAF and SIGRTN on 1.6L. Voltage measurements must be as specified in

VANE AIRFLOW METER VOLTAG

VANE AIRFLOW METER VOLTAGE

VANE AIR TEMPERATURE (VAT) SENSOR

1. Unplug connector from VAF meter. On 1.3L, connect ohmmeter to terminals VAT and ground (Green/Black and Black wires on mating

connector). On 1.6L, connect ohmmeter to VAF meter terminals VAT and SIGRTN (Brown and Blue/Yellow wires on mating
connector).

2. Measure intake air temperature. Measure resistance between specified terminals. See

VANE AIR TEMPERATURE RESISTANCE

Replace VAF if resistance is not as specified.

Throttle Opening

(1)

Ohms

1/8

989

1/4

1104

3/8

1278

1/2

1462

5/8

1480

3/4

1459

7/8

1144

Fully Open

1072

(1)

Resistance may vary by plus or minus 15 percent.

CAUTION:

DO NOT tamper with throttle stop screw at throttle lever. Doing so may result in damage to the
throttle body.

Test Condition

(1)

Cont. Between IDL-TL

Cont. Between PSW-TL

.02" (.5 mm)

Yes

.03" (.7 mm)

Wide Open Throttle

Yes

(1)

Insert specified feeler gauge between throttle adjustment screw and stop lever.

Door Opening

(1)

Volts: 1.3L

(1)

Volts: 1.6L

Fully Closed

.5-1.5

(2)

1/8

.59

3.24

1/4

1.19

5.60

3/8

1.78

5.62

1/2

2.38

5.83

5/8

2.97

6.02

3/4

3.56

6.57

7/8

4.16

7.48

Fully Open

4.5-5.0

7.87

(1)

Voltage may vary by plus or minus 15 percent.

(2)

Voltage not specified.

VANE AIR TEMPERATURE RESISTANCE

(1)

WIDE OPEN THROTTLE SWITCH (1.3L)

This switch is part of the throttle position switch. See THROTTLE POSITION SWITCH (1.3L).

MODULES, RELAYS & SOLENOIDS

MODULES

Ignition Module

See

IGNITION SYSTEM

RELAYS

A/C Clutch Relay

See

MISCELLANEOUS CONTROLS

Cooling Fan Relay

See

MISCELLANEOUS CONTROLS

SOLENOIDS

Canister Purge Solenoid

See

FUEL EVAPORATION

Fuel Pressure Regulator Control Solenoid

See

FUEL DELIVERY

under FUEL SYSTEM.

Idle Speed Control (ISC) Solenoid

This solenoid is part of the Idle Speed Control By-Pass Air (ISC-BPA) valve. See

IDLE CONTROL SYSTEM

under FUEL SYSTEM.

FUEL SYSTEM

FUEL DELIVERY

Fuel Pressure Regulator

1. Measure fuel pressure. See FUEL PRESSURE in BASIC TESTING article in the ENGINE PERFORMANCE Section. Stop engine.

With fuel pressure tester still installed, measure fuel pressure after 5 minutes. If fuel pressure is greater than 21 psi (1.5 kg/cm

) after 5

minutes, go to step 2). Replace fuel pressure regulator if fuel pressure does not remain higher than 21 psi (1.5 kg/cm

2. Remove fuel pressure regulator. Inspect "O" ring, gasket and mounting surfaces for defects. Connect vacuum tester to fuel return tube,

and apply 20 in. Hg vacuum. Replace fuel pressure regulator if vacuum drops by more than 10 in. Hg in 10 seconds. Reinstall fuel
pressure regulator.

3. Again measure fuel pressure. If regulated fuel pressure is higher than specification, check for engine vacuum leaks, damage to fuel

pressure regulator housing or a restricted fuel return line. Replace fuel pressure regulator if no problems are found.

Fuel Pressure Regulator Control Solenoid (1.6L)

1. Locate PRESSURE CONTROL (PRC) solenoid on cowl panel next to canister purge solenoid. Unplug PRC connector. Remove both

vacuum lines. Plug one vacuum port and apply vacuum to remaining port. Replace PRC solenoid if it does not hold vacuum.

2. Connect 12-volt power to PRC terminals. If vacuum drops to zero, PRC solenoid is okay. Replace PRC solenoid if vacuum does not

drop to zero.

FUEL CONTROL

Fuel Injectors

1. Using stethoscope, listen for normal clicking sound at each injector during idle and acceleration. If clicking sound is not heard, remove

electrical connector from injector.

2. Using ohmmeter, measure resistance between injector terminals. See

FUEL INJECTOR RESISTANCE

table. Replace injector if

°F (°C)

Ohms

-4 (-20)

15,000

32 (0)

5200

68 (20)

2500

104 (40)

100

140 (60)

600

176 (80)

300

(1)

Resistance may vary by plus or minus 15 percent

NOTE:

For fuel pressure specifications, see

FUEL PRESSURE SPECIFICATIONS

article.

resistance is not within specifications. If injector resistance is okay, check for 12 volts at each injector connector. Repair or replace
connector as necessary.

FUEL INJECTOR RESISTANCE

IDLE CONTROL SYSTEM

Idle Speed Control By-pass Air (ISC-BPA) Valve

1. Remove ISC-BPA valve from engine. Connect a hose from a hot water tap to coolant inlet nipple on ISC-BPA valve. Blow through

valve air port. Note resistance to airflow.

2. Supply hot water at 130°F (56°C) minimum to ISC-BPA valve and allow time for valve to respond. Blow through valve again. If

resistance to airflow does not increase when valve is hot, replace ISC-BPA valve.

3. Apply 12 volts to solenoid terminals. If solenoid does not click, replace ISC-BPA valve.

IGNITION SYSTEM

PICK-UP COIL

Check continuity of pick-up coil. If continuity exists, replace igniter unit. If continuity does not exist, replace pick-up coil.

TIMING CONTROL SYSTEMS

Advance Components (1.3L)

Ignition timing advance is controlled by the ECA.

Advance Components (1.6L Non-Turbo)

Ignition advance is controlled by a centrifugal advance mechanism within the distributor, and by a vacuum advance mechanism. If centrifugal
advance is not within specification, service the distributor. Replace the vacuum advance mechanism if vacuum advance is not within
specification. See

IGNITION TIMING

. Also see IGNITION TIMING in ADJUSTMENTS article in the ENGINE PERFORMANCE Section.

IGNITION TIMING

Retard Components (1.6L Turbo)

Positive pressure to the vacuum advance cylinder on the distributor retards ignition timing. The ECA also retards ignition timing when it
receives a signal from a Knock Sensor (KS), Knock Control Unit (KC) and related circuitry.

1. Disconnect and plug hoses at distributor. Connect timing light and start engine. Record ignition timing. Tap intake plenum with plastic

mallet while observing ignition timing. If timing retards, knock control circuitry is okay. If timing does not retard, go to step 2).

2. Unplug KC sensor service connector near ECA. Tap intake plenum with plastic mallet while observing ignition timing. If ignition timing

retards, go to step 3). If timing does not retard, go to step 4).

3. Reconnect KC service connector. Tap intake plenum with plastic mallet while observing ignition timing. If ignition timing retards,

replace knock controller. If ignition timing does not retard, go to step 4).

4. Unplug KC service connector near ECA. Temporarily install a known good KS. Tap intake plenum with plastic mallet while observing

ignition timing. If ignition timing retards, replace KS. If ignition timing does not retard, go to step 5).

5. Turn ignition off. Connect BOB. Ensure VPWR and ground wires to KC are okay. Check all KC wiring for shorts or opens. If wiring is

okay, replace KC.

EMISSION SYSTEMS & SUB-SYSTEMS

FUEL EVAPORATION

Canister Purge Solenoid

1. Disconnect vacuum hoses from solenoid. See

Fig. 1

. Blow through port "A". Ensure no air exhausts from port "B".

2. Disconnect 2-wire connector from solenoid. Connect 12 volts to one terminal and ground the other terminal of solenoid. Blow air

though port "A". Ensure air exhausts through port "B".

Application

Ohms

1.3L & 1.6L

12-16

NOTE:

For basic ignition checks, see BASIC TESTING article in the ENGINE PERFORMANCE Section.

Application

Auto. Trans.

Man. Trans.

1.6L Non-Turbo

1-3 @ 850

0-4 @ 850

1.6L Turbo

10-14 @ 850

0-4 @ 850

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