1991 FORD FESTIVA battery

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
man ifo l d .
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 inform ation and operating procedures for the self-diagnostic system , refer to T EST S
W/CODES article in the ENGINE PERFORMANCE Section.
Copyr ight 2009 Mitchell Repair Information Company, LLC. All Rights Reserved.
Article GUID: A00022697
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ASCS
Air Suction Control Solenoid
ASD
Auto Shutdown
ASDM
Air Bag System Diagnostic Module
ASV
Air Suction Valve
A/T
Automatic Transmission/Transaxle
ATC
Automatic Temperature Control
ATDC
After Top Dead Center
ATF
Automatic Transmission Fluid
ATS
Air Temperature Sensor
Aux.
Auxiliary
Avg.
Average
AXOD
Automatic Transaxle Overdrive (Ford Models Only)
"B"
BAC
By-Pass Air Control
BAP
Barometric Absolute Pressure Sensor
BARO
Barometric
Batt.
Battery
Bbl.
Barrel (Example: 4-Bbl.)
BCM
Body Control Module
BHP
Brake Horsepower
BMAP
Page 2 of 15 MITCHELL 1 ARTICLE - GENERAL INFORMATION Commonly Used Abbreviations
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Back To Article
GENERAL INFORMATION
T rouble Shooting - Basic Procedures
* PLEASE READ THIS FIRST *
ACCESSORIES & ELECTRICAL
CHARGING SYSTEM TROUBLE SHOOTING
BASIC CHARGING SYSTEM TROUBLE SHOOTING CHART NOTE:This is GENERAL inform ation. This article is not intended to be specific to any unique situation or
individual vehicle configuration. T he purpose of this T rouble Shooting inform ation is to provide a list
of com m on causes to problem sym ptom s. For m odel-specific T rouble Shooting, refer to SUBJECT ,
DIAGNOST IC, or T EST ING articles available in the section(s) you are accessing.
NOTE:This is GENERAL inform ation. This article is not intended to be specific to any unique situation or
individual vehicle configuration. T he purpose of this T rouble Shooting inform ation is to provide a list
of com m on causes to problem sym ptom s. For m odel-specific T rouble Shooting, refer to SUBJECT ,
DIAGNOST IC, or T EST ING articles available in the section(s) you are accessing.
NOTE:This is GENERAL inform ation. This article is not intended to be specific to any unique situation or
individual vehicle configuration. T he purpose of this T rouble Shooting inform ation is to provide a list
of com m on causes to problem sym ptom s. For m odel-specific T rouble Shooting, refer to SUBJECT ,
DIAGNOST IC, or T EST ING articles available in the section(s) you are accessing.
CONDITION & POSSIBLE CAUSECORRECTION
Vehicle Will Not Start
Dead batteryCheck battery cells, alternator
belt tension and alternator
output
Loose or corroded battery connectionsCheck all charging system
connections
Ignition circuit or switch malfunctionCheck and replace as necessary
Alternator Light Stays On With Engine Running
Loose or worn alternator drive beltCheck alternator drive tension
and condition, See Belt
Adjustment in TUNE-UP article
in the TUNE-UP section
Loose alternator wiring connectionsCheck all charging system
connections
Short in alternator light wiringSee Indicator Warning Lights in
STANDARD INSTRUMENTS
in the ACCESSORIES &
EQUIPMENT section
Defective alternator stator or diodesSee Bench Tests in
ALTERNATOR article
Defective regulatorSee Regulator Check in
ALTERNATOR article
Alternator Light Stays Off With Ignition Switch ON
Blown fuseSee WIRING DIAGRAMS
Defective alternatorSee Testing in ALTERNATOR
article
Defective indicator light bulb or socketSee Indicator Warning Lights in
STANDARD INSTRUMENTS
in the ACCESSORIES &
EQUIPMENT section
Alternator Light Stays OFF With Ignition Switch ON
Short in alternator wiringSee On-Vehicle Tests in
ALTERNATOR article
Defective rectifier bridgeSee Bench Tests in
ALTERNATOR article
Lights or Fuses Burn Out Frequently
Defective alternator wiringSee On-Vehicle Tests in
ALTERNATOR article
Defective regulatorSee Regulator Check in
ALTERNATOR article
Defective batteryCheck and replace as necessary
Ammeter Gauge Shows Discharge
Loose or worn drive beltCheck alternator drive belt
tension and condition. See Belt
Adjustment in TUNE-UP article
in the TUNE-UP section
Defective wiringCheck all wires and wire
Page 1 of 36 MITCHELL 1 ARTICLE - GENERAL INFORMATION Trouble Shooting - Basic Procedures
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IGNITION SYSTEM TROUBLE SHOOTING
connections
Defective alternator or regulatorSee Bench Tests and On-
Vehicle Tests in
ALTERNATOR article
Defective ammeter, or improper ammeter wiring connectionSee Testing in STANDARD
INSTRUMENTS in the
ACCESSORIES &
EQUIPMENT section
Noisy Alternator
Loose drive pulleyTighten drive pulley attaching
nut
Loose mounting boltsTighten all alternator mounting
bolts
Worn or dirty bearingsSee Bearing Replacement
ALTERNATOR article
Defective diodes or statorSee Bench Test in
ALTERNATOR article
Battery Does Stay Charged
Loose or worn drive beltCheck alternator drive belt
tension and condition. See Belt
Adjustment in appropriate
TUNE-UP article in the TUNE-
UP section
Loose or corroded battery connectionsCheck all charging system
connections
Loose alternator connectionsCheck all charging system
connections
Defective alternator or batterySee On-Vehicle Tests and
Bench Tests in ALTERNATOR
article
Add-on electrical accessories exceeding alternator capacityInstall larger alternator
Battery Overcharged-Uses Too Much Water
Defective batteryCheck alternator output and
repair as necessary
Defective alternatorSee On-Vehicle Test and Bench
Tests in ALTERNATOR article
Excessive alternator voltageCheck alternator output and
repair as necessary
NOTE:This is GENERAL inform ation. This article is not intended to be specific to any unique situation or
individual vehicle configuration. T he purpose of this T rouble Shooting inform ation is to provide a list
of com m on causes to problem sym ptom s. For m odel-specific T rouble Shooting, refer to SUBJECT ,
DIAGNOST IC, or T EST ING articles available in the section(s) you are accessing.
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Fig. 2: Ignition Primary Trouble Shooting Chart

STARTER TROUBLE SHOOTING
BASIC STARTER TROUBLE SHOOTING CHART
NOTE:This is GENERAL inform ation. This article is not intended to be specific to any unique situation or
individual vehicle configuration. T he purpose of this T rouble Shooting inform ation is to provide a list
of com m on causes to problem sym ptom s. For m odel-specific T rouble Shooting, refer to SUBJECT ,
DIAGNOST IC, or T EST ING articles available in the section(s) you are accessing.
CONDITION & POSSIBLE CAUSECORRECTION
Starter Fails to Operate
Dead battery or bad connections between starter and batteryCheck battery charge and all
wires and connections to
starter
Ignition switch faulty or misadjustedAdjust or replace ignition
switch
Open circuit between starter switch ignition terminal on starter relayCheck and repair wires and
connections as necessary
Starter relay or starter defectiveSee Testing in STARTER
article
Open solenoid pull-in wireTesting in STARTER article
Starter Does Not Operate and Headlights Dim
Weak battery or dead cellCharge or replace battery as
necessary
Loose or corroded battery connectionsCheck that battery connections
are clean and tight
Internal ground in starter windingsSee Testing in STARTER
article
Grounded starter fieldsSee Testing in STARTERS
Armature rubbing on poleSee STARTER article shoes
Starter Turns but Engine Does Not Rotate
Starter clutch slippingSee STARTER article
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Broken clutch housingSee STARTER article
Pinion shaft rusted or drySee STARTER article
Engine basic timing incorrectSee Ignition Timing in TUNE-
UP article
Broken teeth on engine flywheelReplace flywheel and check for
starter pinion gear damage
Starter Will Not Crank Engine
Faulty overrunning clutchSee STARTER article
Broken clutch housingSee STARTER article
Broken flywheel teethReplace flywheel and check for
starter pinion gear damage
Armature shaft sheared or reduction gear teeth strippedSee STARTER article
Weak batteryCharge or replace battery as
necessary
Faulty solenoidSee On-Vehicle Tests in
STARTER article
Poor groundsCheck all ground connections
for tight and clean connections
Ignition switch faulty or misadjustedAdjust or replace ignition
switch as necessary
Starter Cranks Engine Slowly
Battery weak or defectiveCharge or replace battery as
necessary
Engine overheatedSee ENGINE COOLING
SYSTEM article
Engine oil too heavyCheck that proper viscosity oil
is used
Poor battery-to-starter connectionsCheck that all between battery
and starter are clean and tight
Current draw too low or too highSee Bench Tests in STARTER
article
Bent armature, loose pole shoes screws or worn bearingSee STARTER article
Burned solenoid contactsReplace solenoid
Faulty starterReplace starter
S t a r t e r E n ga ge s E n gin e On l y M o me n t a r il y
Engine timing too far advancedSee Ignition Timing in TUNE-
UP article
Overrunning clutch not engaging properlyReplace overrunning clutch.
See STARTER article
Broken starter clutchSee STARTER article
Broken teeth on engine flywheelReplace flywheel and check
starter pinion gear for damage
Weak drive assembly thrust springSee STARTER article
Weak hold-in coilSee Bench Tests in STARTER
article
Starter Drive Will Not Engage
Defective point assemblySee Testing in STARTER
article
Poor point assembly groundSee Testing in STARTER
article
Defective pull-in coilReplace starter solenoid
Starter Relay Does Not Close
Dead batteryCharge or replace battery as
necessary
Faulty wiringCheck all wiring and
connections leading to relay
Neutral safety switch faultyReplace neutral safety switch
Starter relay faultyReplace starter relay
Starter Drive Will Not Disengage
Starter motor loose on mountingsTighten starter attach bolts
Worn drive end bushingSee STARTER article
Damaged engine flywheel teethReplace flywheel and starter
pinion gear for damage
Drive yolk return spring broken or missingReplace return spring
Faulty ignition switchReplace ignition switch
Insufficient clearance between winding leads to solenoid terminal and main contact in solenoidReplace starter solenoid
Starter clutch not disengagingReplace starter clutch
Ignition starter switchReplace ignition switch
contacts sticking
Starter Relay Operates but Solenoid Does Not
Faulty solenoid switch, switch connections or relayCheck all wiring between relay
and solenoid or replace relay
or solenoid as necessary
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AIR CONDITIONING & HEAT
AIR CONDITIONING TROUBLE SHOOTING
BASIC AIR CONDITIONING TROUBLE SHOOTING CHART
HEATER SYSTEM TROUBLE SHOOTING
BASIC HEATER SYSTEM TROUBLE SHOOTING CHART
Broken lead or loose soldered connectionsRepair wire or wire
connections as necessary
Solenoid Plunger Vibrates When Switch is Engaged
Weak batteryCharge or replace battery as
necessary
Solenoid contacts corrodedClean contacts or replace
solenoid
Faulty wiringCheck all wiring leading to
solenoid
Broken connections inside switch coverRepair connections or replace
solenoid
Open hold-in wiresolenoid
Low Current Draw
Worn brushes or weak brush springsReplace brushes or brush
springs as necessary
High Pitched Whine During Cranking Before Engine Fires but Engine Fires and Cranks Normally
Distance too great between starter pinion and flywheelAlign starter or check that
correct starter and flywheel are
being used
High Pitched Whine After Engine Fires With Key released. Engine Fires and Cranks Normally
Distance too small between starter pinion and flywheelFlywheel runout contributes to
the intermittent nature
WARNING:This is GENERAL inform ation. This article is not intended to be specific to any unique situation or
individual vehicle configuration. T he purpose of this T rouble Shooting inform ation is to provide a list
of com m on causes to problem sym ptom s. For m odel-specific T rouble Shooting, refer to SUBJECT ,
DIAGNOST IC, or T EST ING articles available in the section(s) you are accessing.
CONDITIONPOSSIBLE CAUSE
Compressor Not WorkingCompressor clutch circuit open.
.....Compressor clutch coil inoperative.
.....Poor clutch ground connection.
.....Fan belts loose.
.....Thermostatic switch inoperative.
.....Thermostatic switch not adjusted.
.....Ambient temperature switch open.
.....Superheat fuse blown.
Excessive Noise or VibrationMissing or loose mounting bolts.
.....Bad idler pulley bearings.
.....Fan belts not tightened correctly.
.....Compressor clutch contacting body.
.....Excessive system pressure.
.....Compressor oil level low.
.....Damaged clutch bearings.
.....Damaged reed valves.
.....Damaged compressor.
In su fficien t o r No Co o l in g; Co mp resso r
WorkingExpansion valve inoperative.
.....Heater control valve stuck open.
.....Low system pressure.
.....Blocked condenser fins.
.....Blocked evaporator fins.
.....Vacuum system leak.
.....Vacuum motors inoperative.
.....Control cables improperly adjusted.
.....Restricted air inlet.
.....Mode doors binding.
.....Blower motor inoperative.
.....Temperature above system capacity.
NOTE:This is GENERAL inform ation. This article is not intended to be specific to any unique situation or
individual vehicle configuration. T he purpose of this T rouble Shooting inform ation is to provide a list
of com m on causes to problem sym ptom s. For m odel-specific T rouble Shooting, refer to DIAGNOST IC,
or T EST ING articles available in the section(s) you are accessing.
Page 6 of 36 MITCHELL 1 ARTICLE - GENERAL INFORMATION Trouble Shooting - Basic Procedures
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BASIC WARM ENGINE DRIVEABILITY SYMPTOMS TROUBLE SHOOTING CHART
DIESEL ENGINE TROUBLE SHOOTING
BASIC DIESEL ENGINE TROUBLE SHOOTING CHART
SYSTEMS
Acceleration Sag or Stall
Defective choke control switchReplace choke control switch
Choke vacuum kick setting incorrectReset choke vacuum kick see,
FUEL SYSTEMS
Float level incorrect (too low)Adjust float level, FUEL
SYSTEMS
Accelerator pump defectiveRepair or replace pump see
FUEL SYSTEMS
Secondary throttles not closedInspect lockout adjustment,
see FUEL SYSTEMS
Sag or Stall After Warmup
Defective choke control switchReplace choke control switch,
see FUEL SYSTEMS
Defective accelerator pumpReplace pump, see FUEL
SYSTEMS
Float level incorrect (too low)Adjust float level, see FUEL
SYSTEMS
Backfiring & Black Smoke
Plugged heat crossover systemRemove restriction
CONDITION & POSSIBLE CAUSECORRECTION
Hesitation With Small Amount of Gas Pedal Movement
Vacuum leakInspect vacuum lines
Accelerator pump weak or inoperableReplace pump, see FUEL
SYSTEMS
Float level setting too lowReset float level, see,FUEL
SYSTEMS
Metering rods sticking or bindingInspect and/or replace rods,
see FUEL SYSTEMS
Carburetor idle or transfer system pluggedInspect system and remove
restriction
Frozen or binding heated air inletInspect heated air door for
binding
Hesitation With Heavy Gas Pedal Movement
Defective accelerator pumpReplace pump, see FUEL
SYSTEMS
Metering rod carrier sticking or bindingRemove restriction
Large vacuum leakInspect vacuum system and
repair leak
Float level setting too lowReset float level, see FUEL
SYSTEMS
Defective fuel pump, lines or filterInspect pump, lines and filter
Air door setting incorrectAdjust air door setting, see
FUEL
NOTE:This is GENERAL inform ation. This article is not intended to be specific to any unique situation or
individual vehicle configuration. T he purpose of this T rouble Shooting inform ation is to provide a list
of com m on causes to problem sym ptom s. For m odel-specific T rouble Shooting, refer to SUBJECT ,
DIAGNOST IC, or T EST ING articles available in the section(s) you are accessing.
NOTE:Diesel engines m echanical diagnosis is the sam e as gasoline engines for item s such as noisy valves,
bearings, pistons, etc. T he following trouble shooting covers only item s pertaining to diesel engines.
CONDITION & POSSIBLE CAUSECORRECTION
Engine Won't Crank
Bad battery connections or dead batteriesCheck connections and/or
replace batteries
Bad starter connections or bad starterCheck connections and/or
replace starter
Engine Cranks Slowly, Won't Start
Bad battery connections or dead batteriesCheck connections and/or
replace batteries
Engine oil too heavyReplace engine oil
Engine Cranks Normally, But Will Not Start
Glow plugs not functioningCheck glow plug system, see
FUEL SYSTEMS
Glow plug control not functioningCheck controller, see FUEL
SYSTEMS
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