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Ford Festiva. Instruction - part 63

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GENERAL INFORMATION

TROUBLE SHOOTING

* PLEASE READ THIS FIRST *

ENGINE PERFORMANCE

TUNE-UP TROUBLE SHOOTING

NOTE:

This article is generic in nature and all information does not apply to all vehicles. For vehicle specific
information, see the appropriate articles in the ENGINE PERFORMANCE category.

NOTE:

This article is generic in nature and all information does not apply to all vehicles. For vehicle specific
information, see the appropriate articles in the ENGINE PERFORMANCE category.

Problem & Possible Cause

Action

Carbon Fouled Plugs

Clogged Air Filter

Replace Air Filter

Incorrect Idle Speed

Reset Idle Speed

Faulty Ignition Wiring

Replace Ignition Wiring

Sticky Valves/Worn Valve Seal

Check Valve Train

Fuel Injection Operation

Check Fuel Injection

Wet/Oil Fouled Plugs

Worn Rings/Pistons

Overhaul/Replace Engine

Excessive Cylinder Wear

Overhaul/Replace Engine

Plug Gap Bridged

Combustion Chamber Carbon Deposits

Clean Combustion

Chamber

Blistered Electrode

Engine Overheating

Check Cooling System

Loose Spark Plugs

Clean/Torque Plugs

Over-Advanced Timing

Reset Timing

Wrong Plug Heat Range

Install Correct Plug

Melted Electrodes

Incorrect Timing

Reset Timing

Burned Valves

Replace Valves

Engine Overheating

Check Cooling System

Wrong Plug Heat Range

Install Correct Plug

Engine Won't Start

Loose Connections

Check Connections

No Power

Check Fuses/Battery

Loose/Worn Timing Belt/Chain/Gears

Check Belt/Chain/Gears

Engine Runs Rough

Leaky/Clogged Fuel Injectors

Repair Fuel Injectors

Leaky/Clogged Fuel Lines

Repair Fuel Lines

Clogged Fuel Filter

Replace Fuel Filter

Incorrect Timing

Reset Timing/Check

Advance

Faulty Plugs/Wires

Replace Plugs/Wires

Uneven Compression

Overhaul/Replace Engine

Poor Acceleration

Incorrect Ignition Timing

Reset Timing

Leaky Valves

Check Compression

Component Failure

Spark Arcing

Replace Faulty Part

Defective Pick-Up Coil

Replace Pick-Up Coil

Defective Ignition Coil

Replace Ignition Coil

Defective Control Unit

Replace Control Unit

Ignition Diagnosis By Scope Pattern

All Firing Lines Abnormally High

Retarded Ignition Timing

Reset Ignition Timing

Lean Air/Fuel Mixture

Adjust Fuel Mixture

High Secondary Resistance

Repair Secondary

Ignition

All Firing Lines Abnormally Low

Rich Air/Fuel Mixture

Adjust Air/Fuel Mixture

Arcing Coil Wire

Replace Coil Wire

Cracked Coil

Replace Coil

Low Coil Output

Replace Coil

Low Compression

Check/Repair Engine

FUEL INJECTION TROUBLE SHOOTING

Several High Firing Lines

Fuel Mixture Unbalanced

Check Fuel System

EGR Valve Stuck Open

Clean/Replace EGR

Valve

High Plug Wire Resistance

Replace Plug Wire

Cracked/Broken Plugs

Replace Plugs

Intake Vacuum Leak

Repair Leak

Several Low Firing Lines

Fuel Mixture Unbalanced

Adjust Fuel Mixture

Plug Wires Arcing

Replace Plug Wires

Cracked Coil Arcing

Replace Coil

Uneven Compression

Check/Repair Engine

Faulty Spark Plugs

Replace Plugs

Cylinders Not Firing

Cracked Distributor Cap

Replace Cap

Shorted Plug Wires

Replace Plug Wires

Mechanical Engine Fault

Check/Repair Engine

Spark Plugs Fouled

Replace Plugs

Carbon Track in Distributor Cap

Replace Cap

Hard Starting

Defective Ignition Coil(s)

Replace Coil(s)

Fouled Spark Plugs

Replace Plugs

Incorrect Timing

Reset Ignition Timing

NOTE:

This article is generic in nature and all information does not apply to all vehicles. For vehicle specific
information, see the appropriate articles in the ENGINE PERFORMANCE category.

Problem & Possible Cause

Action

Cold Start Valve Inoperative

Test Cold Start Valve

Poor Vacuum/Electrical Connection

Repair Connections

Contaminated Fuel

Test Fuel for Water/Alcohol

Bad Fuel Pump Relay/Circuit

Test Relay/Wiring

Battery Voltage Low

Charge/Test Battery

Low Fuel Pressure

Test Press. Regulator/Pump

No Distributor Reference Pulse

Repair Ignition System

Coolant Temp. Sensor Defective

Test Temp. Sensor/Circuit

No Power To Injectors

Check Injector Fuse/Relay

Hard Starting

Defective Idle Air Control (IAC)

Test IAC and Circuit

EGR Valve Open

Test EGR Valve/Control

Circuit

Restricted Fuel Lines

Inspect/Replace Fuel Lines

Poor MAP Sensor Signal

Test MAP Sensor/Circuit

Engine Stalls During Parking Maneuver

Check P.S. Press. Switch

Rough Idle

Dirty Fuel Injectors

Clean/Replace Injectors

Poor MAP Sensor Signal

Test MAP Sensor/Circuit

Intermittent Fuel Injector Operation

Check Harness Connectors

Erratic Vehicle Speed Sensor Inputs

Harness Too Close to Plug

Wires

Poor O

Sensor Signal

Test O

Sensor/Circuit

Faulty PCV System

Check PCV Valve and

Hoses

Poor Acceleration

Weak Fuel Pump

Replace Fuel Pump

Dirty Fuel Injectors

Clean/Replace Injectors

Excessive Intake Valve Deposits

Clean Intake System

Poor High Speed Operation

Low Fuel Pump Volume

Faulty Fuel Pump/Filter

Poor MAP Sensor Signal

Test Speed Sensor/Circuit

Acceleration Ping/Knock

Faulty EGR System

Check EGR Valve and

Hoses

Poor Knock Sensor Signal

Test Knock Sensor/Circuit

Poor Baro Sensor Signal

Test Baro Sensor/Circuit

Improper Ignition Timing

Adjust Timing

Engine Overheating

Check Cooling System

Poor Quality Fuel

Use Different Fuel

Carbon Build-Up

Decarbon Engine

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GENERAL INFORMATION

Computer Relearn Procedures

COMPUTER RELEARN PROCEDURES

Vehicles equipped with engine or transmission computers may require a relearn procedure after vehicle battery is disconnected. Many vehicle
computers memorize and store vehicle operation patterns for optimum driveability and performance. When vehicle battery is disconnected,
this memory is lost. The computer will use default data until new data from each key start is stored. As computer memorizes vehicle operation
for each new key start, driveability is restored. Vehicle computers may memorize vehicles operation patterns for 40 of more key starts.

Customers often complain of driveability problems during relearn stage because vehicle acts differently then before being serviced. Depending
on type and make of vehicle and how it is equipped, the following complaints (driveability problems) may exist:



Harsh Or Poor Shift Quality



Rough Or Unstable Idle



Hesitation Or Stumble



Rich Or Lean Running



Poor Fuel Mileage

These symptoms and complaints should disappear after a number of drive cycles have been memorized. To reduce the possibility of
complaints, after any service which requires battery power to be disconnected, vehicle should be road tested.

GENERIC COMPUTER RELEARN PROCEDURES

Some manufacturers identify a specific relearn procedure which will help establish suitable driveability during relearn stage. These procedures
are especially important if vehicle is equipped with and electronically controlled automatic transmission or transaxle. Always complete
procedure before returning vehicle to customer. The following general procedures are to be used if driveability problems are encountered after
power loss or battery has been disconnected. These procedures may provide an aid in eliminating these problems.

Automatic Transmission



Set parking brake, start engine in "P" or "N" position. Warm-up vehicle to normal operating temperature or until cooling fan cycles.



Allow vehicle to idle for one minute in "N" position. Select "D" and allow engine to idle for one minute.



Accelerate at normal throttle position (20-50%) until vehicle shifts into top gear.



Cruise at light to medium throttle.



Decelerate to a stop, allowing vehicle to downshift, and use brakes normally.



Process may be repeated as necessary.

Instruction Transmission



Place transmission in Neutral position.



Ensure emergency brake has been set and all accessories are turned off.



Start engine and bring to normal operating temperature.



Allow vehicle to idle in Neutral for one minute.



Initial relearn is complete, and process will be completed during normal driving.

Article GUID: A00012612

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GENERAL INFORMATION

Drive Axle Noise Diagnosis

* PLEASE READ THIS FIRST *

UNRELATED NOISES

Some driveline trouble symptoms are also common to the engine, transmission, wheel bearings, tires and other parts of the vehicle. Make sure
that cause of trouble actually is in the drive axle before adjusting, repairing, or replacing any parts.

NON-DRIVE AXLE NOISES

A few conditions can sound just like drive axle noise and have to be considered in pre-diagnosis. The 4 most common noises are exhaust, tires,
CV/universal joints and trim moldings.

In certain conditions, the pitch of exhaust gases may sound like gear whine. At other times, it may be mistaken for a wheel bearing rumble.

Tires, especially radial and snow tires, can have a high-pitched tread whine or roar, similar to gear noise. Also, some non-standard tires with an
unusual tread construction may emit a roar or whine.

Defective CV/universal joints may cause clicking noises or excessive driveline play that can be improperly diagnosed as drive axle problems.

Trim and moldings can also cause a whistling or whining noise. Ensure that none of these components are causing the noise before
disassembling the drive axle.

GEAR NOISE

A "howling" or "whining" noise from the ring and pinion gear can be caused by an improper gear pattern, gear damage, or improper bearing
preload. It can occur at various speeds and driving conditions, or it can be continuous.

Before disassembling axle to diagnose and correct gear noise, make sure that tires, exhaust, and vehicle trim have been checked as possible
causes.

CHUCKLE

This is a particular rattling noise that sounds like a stick against the spokes of a spinning bicycle wheel. It occurs while decelerating from 40
MPH and usually can be heard until vehicle comes to a complete stop. The frequency varies with the speed of the vehicle.

A chuckle that occurs on the driving phase is usually caused by excessive clearance due to differential gear wear, or by a damaged tooth on the
coast side of the pinion or ring gear. Even a very small tooth nick or a ridge on the edge of a gear tooth is enough to cause the noise.

This condition can be corrected simply by cleaning the gear tooth nick or ridge with a small grinding wheel. If either gear is damaged or scored
badly, the gear set must be replaced. If metal has broken loose, the carrier and housing must be cleaned to remove particles that could cause
damage.

KNOCK

This is very similar to a chuckle, though it may be louder, and occur on acceleration of deceleration. Knock can be caused by a gear tooth that
is damaged on the drive side of the ring and pinion gears. Ring gear bolts that are hitting the carrier casting can cause knock. Knock can also be
due to excessive end play in the axle shafts.

NOTE:

This is GENERAL information. This article is not intended to be specific to any unique situation or
individual vehicle configuration. For model-specific information see appropriate articles where
available.

NOTE:

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