check engine FORD FESTIVA 1991 Manual PDF

bolts
Noisy Pistons and Rings
Excessive piston-to-bore clearanceInstall larger pistons, See
ENGINES
Bore tapered or out-of-roundRebore block
Piston ring brokenReplace piston rings, See
ENGINES
Piston pin loose or seizedReplace piston pin, See
ENGINES
Connecting rods misalignedRealign connecting rods
Ring side clearance too loose or tightReplace with larger or smaller
rings
Carbon build-up on pistonRemove carbon
Noisy Valve Train
Worn or bent push rodsReplace push rods, See
ENGINES
Worn rocker arms or bridged pivotsReplace push rods, See
ENGINES
Dirt or chips in valve liftersRemove lifters and remove
dirt/chips
Excessive valve lifter leak-downReplace valve lifters, See
ENGINES
Valve lifter face wornReplace valve lifters, See
ENGINES
Broken or cocked valve springsReplace or reposition springs
Too much valve stem-to-guide clearanceReplace valve guides, See
ENGINES
Valve bentReplace valve, See ENGINES
Loose rocker armsRetighten rocker arms, See
ENGINES
Excessive valve seat run-outReface valve seats, See
ENGINES
Missing valve lockInstall new valve lock
Excessively worn camshaft lobesReplace camshaft, See
ENGINES
Plugged valve lifter oil holesEliminate restriction or
replace lifter
Faulty valve lifter check ballReplace lifter check ball, See
ENGINES
Rocker arm nut installed upside downRemove and reinstall correctly
Valve lifter incorrect for engineRemove and replace valve
lifters
Faulty push rod seat or lifter plungerReplace plunger or push rod
Noisy Valves
Improper valve lashRe-adjust valve lash, See
ENGINES
Worn or dirty valve liftersClean and/or replace lifters
Wo r n va l ve gu id e sReplace valve guides, See
ENGINES
Excessive valve seat or face run-outReface seats or valve face
Worn camshaft lobesReplace camshaft, See
ENGINES
Loose rocker arm studsRe-tighten rocker arm studs,
See ENGINES
Bent push rodsReplace push rods, See
ENGINES
Broken valve springsReplace valve springs, See
ENGINES
Burned,Sticking or Broken Valves
Weak valve springs or warped valvesReplace valves and/or springs,
See ENGINES
Improper lifter clearanceRe-adjust clearance or replace
lifters
Worn guides or improper guide clearanceReplace valve guides, See
ENGINES
Out-of-round valve seats or improper seat widthRe-grind valve seats
Gum deposits on valve stems, seats or guideRemove deposits
Improper spark timingRe-adjust spark timing
Broken Pistons/Rings
Undersize pistonsReplace with larger pistons,
See ENGINES
Wrong piston ringsReplace with correct rings,
See ENGINES
Out-of-round cylinder boreRe-bore cylinder bore
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ENGINE PERFORMANCE
CARBURETOR TROUBLE SHOOTING:
BASIC COLD START SYMPTOMS TROUBLE SHOOTING CHART
BASIC HOT START SYMPTOMS TROUBLE SHOOTING CHART
BASIC COLD ENGINE DRIVEABILITY SYMPTOMS TROUBLE SHOOTING CHART
Improper connecting rod alignmentRemove and realign
connecting rods
E xc e ssive l y wo r n r in g gr o o ve sReplace pistons, See
ENGINES
Improperly assembled piston pinsRe-assemble pin-to-piston,
See ENGINES
Insufficient ring gap clearanceInstall new rings, See
ENGINES
Engine overheatingCheck cooling system
Incorrect ignition timingRe-adjust ignition timing, See
TUNE-UP
Excessive Exhaust Noise
Leaks at manifold to head, or to pipeReplace manifold or pipe
ga ske t
Exhaust manifold cracked or brokenReplace exhaust manifold, See
ENGINES
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
Engine Won't Start
Choke not closingCheck choke operation, see
FUEL SYSTEMS
Choke linkage bentCheck linkage, see FUEL
SYSTEM
Engine Starts, Then Dies
Choke vacuum kick setting too wideCheck setting and adjust see,
FUEL SYSTEMS
Fast idle RPM too lowReset RPM to specification,
see TUNE-UP
Fast idle cam index incorrectReset fast idle cam index, see
FUEL SYSTEMS
Vacuum leakInspect vacuum system for
leaks
Low fuel pump outletRepair or replace pump, see
FUEL SYSTEMS
Low carburetor fuel levelCheck float setting see FUEL
SYSTEM
Engine Quits Under Load
Choke vacuum kick setting incorrectReset vacuum kick setting,see
FUEL SYSTEMS
Fast idle cam index incorrectReset fast idle cam index, see
FUEL SYSTEM
Incorrect hot fast idle speed RPMReset fast idle RPM, see
TUNE-UP
Engine Starts, Runs Up, Then Idles, Slowly With Black Smoke
Choke vacuum kick set too narrowReset vacuum kick, see FUEL
SYSTEMS
Fast idle cam index incorrectReset fast idle cam index, see
FUEL SYSTEMS
Hot fast idle RPM too lowReset fast idle RPM, see
TUNE-UP
CONDITION & POSSIBLE CAUSECORRECTION
Engine Won't Start
Engine floodedAllow fuel to evaporate
CONDITION & POSSIBLE CAUSECORRECTION
Engine Stalls in Gear
Choke vacuum kick setting incorrectReset choke vacuum kick, see
FUEL SYSTEMS
Fast idle RPM incorrectReset fast idle RPM, see
TUNE-UP
Fast idle cam index incorrectReset fast idle cam see FUEL
Page 13 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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Fuel not injected into cylindersCheck fuel injectors, see FUEL
SYSTEMS
No fuel to injection pumpCheck fuel delivery system
Fuel filter blockedReplace fuel filter
Fuel tank filter blockedReplace fuel tank filter
Fuel pump not operatingCheck pump operation and/or
replace pump
Fuel return system blockedInspect system and remove
restriction
No voltage to fuel solenoidCheck solenoid and
connections
Incorrect or contaminated fuelReplace fuel
Incorrect injection pump timingRe-adjust pump timing, see
FUEL SYSTEMS
Low compressionCheck valves, pistons, rings,
see ENGINES
Injection pump malfunctionInspect and/or replace
injection pump
Engine Starts, Won't Idle
Incorrect slow idle adjustmentReset idle adjustment, see
TUNE-UP
Fast idle solenoid malfunctioningCheck solenoid and
connections
Fuel return system blockedCheck system and remove
restrictions
Glow plugs go off too soonSee glow plug diagnosis in
FUEL SYSTEMS
Injection pump timing incorrectReset pump timing, see FUEL
SYSTEMS
No fuel to injection pumpCheck fuel delivery system
Incorrect or contaminated fuelReplace fuel
Low compressionCheck valves, piston, rings, see
ENGINES
Injection pump malfunctionReplace injection pump, see
FUEL SYSTEMS
Fuel solenoid closes in RUN positionCheck solenoid and
connections
Engines Starts/Idles Rough W/out Smoke or Noise
Incorrect slow idle adjustmentReset slow idle, see TUNE-UP
Injection line fuel leaksCheck lines and connections
Fuel return system blockedCheck lines and connections
Air in fuel systemBleed air from system
Incorrect or contaminated fuelReplace fuel
Injector nozzle malfunctionCheck nozzles, see FUEL
SYSTEMS
Engines Starts and Idles Rough W/out Smoke or Noise, But Clears After Warm-Up
Injection pump timing incorrectReset pump timing, see FUEL
SYSTEMS
Engine not fully broken inPu t mo re mil es o n en gin e
Air in systemBleed air from system
Injector nozzle malfunctionCheck nozzles, see FUEL
SYSTEMS
Engine Idles Correctly, Misfires Above Idle
Bl o cked fu el fil t erReplace fuel filter
Injection pump timing incorrectReset pump timing, see FUEL
SYSTEMS
Incorrect or contaminated fuelReplace fuel
Engine Won't Return To Idle
Fast idle adjustment incorrectReset fast idle, see TUNE-UP
Internal injection pump malfunctionReplace injection pump, see
FUEL SYSTEMS
External linkage bindingCheck linkage and remove
binding
Fuel Leaks On Ground
Loose or broken fuel lineCheck lines and connections
Internal injection pump seal leakReplace injection pump, see
FUEL SYSTEMS
Cylinder Knocking Noise
Injector nozzles sticking openTest injectors, see FUEL
SYSTEMS
Very low nozzle opening pressureTest injectors and/or replace
Loss of Engine Power
Restricted air intakeRemove restriction
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VACUUM PUMP DIAGNOSIS
FUEL INJECTION TROUBLE SHOOTING
BASIC FUEL INJECTION TROUBLE SHOOTING CHART
EGR valve malfunctionReplace EGR valve
Blocked or damaged exhaust systemRemove restriction and/or
replace components
Blocked fuel tank filterReplace filter
Restricted fuel filterRemove restriction and/or
replace filter
Block vent in gas capRemove restriction and/or
replace cap
Tank-to-injection pump fuel supply blockedCheck fuel lines and
connections
Blocked fuel return systemRemove restriction
Incorrect or contaminated fuelReplace fuel
Blocked injector nozzlesCheck nozzle for blockage, see
FUEL SYSTEMS
Low compressionCheck valves, rings, pistons,
see ENGINES
Loud Engine Noise With Black Smoke
Basic timing incorrectReset timing, see FUEL
SYSTEMS
EGR valve malfunctionReplace EGR valve
Internal injection pump malfunctionReplace injection pump, see
FUEL SYSTEMS
Incorrect injector pump housing pressureCheck pressure, see FUEL
SYSTEMS
Engine Overheating
Cooling system leaksCheck cooling system and
repair leaks
Belt slipping or damagedCheck tension and/or replace
belt
Thermostat stuck closedRemove and replace
thermostat, see ENGINE
COOLING
Head gasket leakingReplace head gasket
Oil Light on at Idle
Low oil pump pressureCheck oil pump operation, see
ENGINES
Oil cooler or line restrictedRemove restriction and/or
replace cooler
Engine Won't Shut Off
Injector pump fuel solenoid does not return fuel valve to OFF positionRemove and check solenoid
and replace if needed
CONDITION & POSSIBLE CAUSECORRECTION
Excessive Noise
Loose pump-to-drive assembly screwsTighten screws
Loose tube on pump assemblyTighten tube
Valves not functioning properlyReplace valves
Oil Leakage
Loose end plugTighten end plug
Bad seal crimpRemove and re-crimp seal
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
Engine Won't Start (Cranks Normally)
Cold start valve inoperativeTest valve and circuit
Poor connection;vacuum or wiringCheck vacuum and electrical
connections
Contaminated fuelTest fuel for water or alcohol
Defective fuel pump relay or circuitTest relay and wiring
Battery too lowCharge and test battery
Low fuel pressureTest pressure regulator and
fuel pump, check for restricted
lines and filters
No distributor reference pulsesRepair ignition system as
necessary
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IGNITION SYSTEM TROUBLE SHOOTING
Open coolant temperature sensor circuitTest sensor and wiring
Shorted W.O.T. switch in T.P.S.Disconnect W.O.T. switch,
engine should start
Defective ECMReplace ECM
Fuel tank residual pressure valve leaksTest for fuel pressure drop
after shut down
Hard Starting
Disconnected hot air tube to air cleanerReconnect tube and test
control valve
Defective Idle Air Control (IAC) valveTest valve operation and
circuit
Shorted, open or misadjusted T.P.S.Test and adjust or replace
T.P.S.
EGR valve openTest EGR valve and control
circuit
Poor Oxygen sensor signalTest for shorted or circuit
Incorrect mixture from PCV systemTest PCV for flow, check
sealing of oil filter cap
Poor High Speed Operation
Low fuel pump volumeFaulty pump or restricted fuel
lines or filters
Poor MAP sensor signalTest MAP sensor, vacuum
hose and wiring
Poor Oxygen sensor signalTest for shorted or open
sensor or circuit
Open coolant temperature sensor circuitTest sensor and wiring
Faulty ignition operationCheck wires for cracks or poor
con- nections, test secondary
voltage with oscilloscope
Contaminated fuelTest fuel for water or alcohol
Intermittent ECM groundTest ECM ground connection
for resistance
Restricted air cleanerReplace air cleaner
Restricted exhaust systemTest for exhaust manifold back
pressure
Poor MAF sensor signalCheck leakage between sensor
and manifold
Poor VSS signalIf tester for ALCL hook-up is
available check that VSS
reading matches speedometer
Ping or Knock on Acceleration
Poor Knock sensor signalTest for shorted or open
sensor or circuit
Poor Baro sensor signalTest for shorted or open
sensor or circuit
Improper ignition timingSee VEHICLE EMISSION
CONTROL LABEL (where
applicable)
Check for engine overheating problemsLow coolant, loose belts or
electric cooling fan inoperative
NOTE:For additional electronic fuel injection trouble shooting inform ation, see the appropriate article in the
ENGINE PERFORMANCE section (not all vehicles have Com puter Engine Control articles). Inform ation
is provided there for diagnosing fuel system problem s on vehicles with electronic fuel injection.
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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Starter Turns but Engine Does Not Rotate
Starter clutch slippingSee STARTER article
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 bearingsSee 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 switch contacts stickingReplace ignition switch
Starter Relay Operates but Solenoid Does Not
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TUNE-UP TROUBLE SHOOTING - GAS ENGINE VEHICLES
BASIC SPARK PLUG TROUBLE SHOOTING CHARTS
Faulty solenoid switch, switch connections or relayCheck all wiring between
relay and solenoid or replace
relay or solenoid as necessary
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 wireReplace solenoid
Low Current Draw
Worn brushes or weakReplace 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
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
Normal Spark Plug Condition
Light Tan or Gray depositsNo Action
Electrode not burned or fouledNo Action
Gap tolerance not changedNo Action
Cold Fouling or Carbon Deposits
Overrich air/fuel mixtureAdjust air/fuel mixture, see
ENGINE PERFORMANCE
section
Faulty chokeReplace choke assembly, see
ENGINE PERFORMANCE
section
Clogged air filterClean and/or replace air filter
Incorrect idle speed or dirty carburetorReset idle speed and/ or clean
carburetor
Faulty ignition wiresReplace ignition wiring
Prolonged operation at idleShut engine off during long
idle
Sticking valves or worn valve guide sealsCheck valve train
Wet Fouling or Oil Deposits
Worn rings and pistonsInstall new rings and pistons
Excessive cylinder wearRebore or replace block
Excessive valve guide clearanceWorn or loose bearing
Gap Bridged
Deposits in combustion chamber becoming fused to electrodeClean combustion chamber of
deposits
Blistered Electrode
Engine overheatingCheck cooling system
Wrong type of fuelReplace with correct fuel
Loose spark plugsRetighten spark plugs
Over-advanced ignition timingReset ignition timing see
ENGINE PERFORMANCE
Pre-Ignition or Melted Electrodes
Incorrect type of fuelReplace with correct fuel
Incorrect ignition timingReset ignition timing see
ENGINE PERFORMANCE
Burned valvesReplace valves
Engine OverheatingCheck cooling system
Wrong type of spark plug, too hotReplace with correct spark
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BASIC ELECTRONIC IGNITION TROUBLE SHOOTING CHARTS
BASIC ELECTRONIC IGNITION TROUBLE SHOOTING CHARTS - USING OSCILLOSCOPE PATTERNS
plug, see ENGINE
PERFORMANCE
Chipped Insulators
Severe detonationCheck for over-advanced
timing or combustion
Improper gapping procedureRe-gap spark plugs
Rust Colored Deposits
Additives in unleaded fuelTry different fuel brand
Water In Combustion Chamber
Blown head gasket or cracked headRepair or replace head or head
ga ske t
NOTE:Before diagnosing an electronic ignition system , ensure that all wiring is connected properly between
distributor, wiring connector and spark plugs. Ignition problem will show up either as: Engine Will Not
Start or Engine Runs Rough.
CONDITION & POSSIBLE CAUSECORRECTION
Engine Won't Start
Open circuit between distributor and bulkhead connectorRepair circuit
Open circuit between bulkhead connector and ignition switchRepair circuit
Open circuit between ignition switch and starter solenoidRepair circuit
Engine Runs Rough
Fuel lines leaking or cloggedTigh t e n fit t in g, r e mo ve
restriction
Initial timing incorrectReset ignition timing see
ENGINE PERFORMANCE
Centrifugal advance malfunctionRepair distributor advance
Defective spark plugs or wiringReplace plugs or plug wiring
Component Failure
Spark arc-over on cap, rotor or coilReplace cap, rotor or or coil
Defective pick-up coilReplace pick-up coil
Defective ignition coilReplace ignition coil
Defective vacuum unitReplace vacuum unit
Defective control moduleReplace control module
CONDITION & POSSIBLE CAUSECORRECTION
Firing Voltage Lines are the Same, but Abnormally High
Retarded ignition timingReset ignition timing, see
ENGINE PERFORMANCE
section
Fuel mixture too leanReadjust carburetor, see
ENGINE PERFORMANCE
High resistance in coil wireReplace coil wire
Corrosion in coil tower terminalClean and/or replace coil
Corrosion in distributor coil terminalClean and/or replace
distributor cap
Firing Voltage Lines are the Same but Abnormally Low
Fuel mixture too richReadjust carburetor, see
ENGINE PERFORMANCE
Breaks in coil wire causing arcingReplace coil wire
Cracked coil tower causing arcingReplace coil
Low coil outputReplace coil
Low engine compressionDetermine cause and repair
One or More, But Not All Firing Voltage Lines are Higher Than Others
Carburetor idle mixture not balancedReadjust carburetor, see
ENGINE PERFORMANCE
EGR valve stuck openClean and/or replace valve
High resistance in spark plug wiresReplace spark plug wires
Cracked or broken spark plug insulatorReplace spark plugs
Intake vacuum leakRepair leak
Defective spark plugsReplace spark plugs
Corroded spark plug terminalsReplace spark plugs
One or More, But Not All Firing Voltage Lines Are Lower Than Others
Curb idle mixture not balancedReadjust carburetor, see
ENGINE PERFORMANCE
Breaks in plug wiresReplace plug wires causing
arcing
Cracked coil tower causing arcingReplace coil
Low compressionDetermine cause and repair
Defective spark plugsReplace spark plugs
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BASIC DRIVEABILITY PROBLEMS TROUBLE SHOOTING
Corroded spark plugsReplace spark plugs
Cylinders Not Firing
Cracked distributor cap terminalsReplace distributor cap
Shorted spark plug wireDetermine cause and repair
Mechanical problem in engineDetermine cause and repair
Defective spark plugsReplace spark plugs
Spark plugs fouledReplace spark plugs
CONDITION & POSSIBLE CAUSECORRECTION
Hard Starting
Binding carburetor linkageEliminate binding
Binding choke linkageEliminate binding
Binding choke pistonEliminate binding
Restricted choke vacuumCheck vacuum lines for
blockage
Worn or dirty needle valve and seatClean carburetor, see ENGINE
PERFORMANCE
Float stickingReadjust or replace float see
the ENGINE
PERFORMANCE section
Incorrect choke adjustmentReset choke adjustment see
ENGINE PERFORMANCE
Defective coilReplace coil
Improper spark plug gapRegap spark plugs
Incorrect ignition timingReset ignition timing see
ENGINE PERFORMANCE
Detonation
Over-advanced ignition timingReset ignition timing see
ENGINE PERFORMANCE
Defective spark plugsReplace spark plugs
Fuel lines cloggedClean fuel lines
EGR system malfunctionCheck and repair EGR system
PCV system malfunctionRepair PCV system
Vacuum leaksCheck and repair vacuum
system
Loose fan beltsTighten or replace fan belts,
see ENGINE
PERFORMANCE
Restricted airflowRemove restriction
Vacuum advance malfunctionCheck distributor operation
Dieseling
Binding carburetor linkageEliminate binding
Binding throttle linkageEliminate blinding
Binding choke linkage or fast idle camEliminate binding
Defective idle solenoidReplace idle solenoid see
ENGINE PERFORMANCE
Improper base idle speedReset idle speed, see see
ENGINE PERFORMANCE
Incorrect ignition timingReset ignition timing see
ENGINE PERFORMANCE
Incorrect idle mixture settingReset idle mixture, see
ENGINE PERFORMANCE
Faulty Acceleration
Incorrect ignition timingReset ignition timing see
ENGINE PERFORMANCE
Engine cold and choke too leanAdjust choke and allow engine
to warm-up
Defective spark plugsReplace spark plugs
Defective coilReplace coil
Faulty Low Speed Operation
Clogged idle transfer slotsClean idle transfer slots, see
FUEL
Restricted idle air bleeds and passagesDisassemble and clean
carburetor, see FUEL
Clogged air cleanerReplace air filter
Defective spark plugsReplace spark plugs
Defective ignition wiresReplace ignition wire see
ENGINE PERFORMANCE
Defective distributor capReplace distributor cap
Faulty High Speed Operation
Incorrect ignition timingReset ignition timing see
ENGINE PERFORMANCE
Page 23 of 36 MITCHELL 1 ARTICLE - GENERAL INFORMATION Trouble Shooting - Basic Procedures
3/10/2009 http://www.eautorepair.net/app/PrintItems.asp?S0=2097152&S1=0&SG=%7B9B990D68%2D660A%2D45E9%2D8F46%2DE
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