belt FORD FESTIVA 1991 Workshop Manual

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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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
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Worn shaft serrationsSee STEERING COLUMN
article
Growl in Steering Pump
Excessive pressure in hosesRestricted hoses, see POWER
STEERING GEAR article
Scored pressure platesSee POWER STEERING
GEAR article
Scored thrust plates or rotorSee POWER STEERING
GEAR article
Extreme wear of cam ringSee POWER STEERING
GEAR article
Rattle in Steering Pump
Vanes not installedSee POWER STEERING
PUMP article
Vanes sticking in rotorSee POWER STEERING
PUMP article
Swish noise in Pump
Defective flow control valveSee POWER STEERING
PUMP article
Groan in Steering Pump
Air in fluidSee POWER STEERING
PUMP article
Poor pressure hose connectionTighten and check, replace if
necessary
Squawk When Turning
Damper "O" ring on valve spool cutSee POWER STEERING
PUMP article
Moan or Whine in Pump
Pump shaft bearing scoredReplace bearing and fluid
Air in fluid or fluid level lowSee POWER STEERING
PUMP article
Hose or column groundedCheck and replace if necessary
Cover "O" ring missing or damagedSee POWER STEERING
PUMP article
Valve cover baffle missing or damagedSee POWER STEERING
PUMP article
Interference of components in pumpSee POWER STEERING
PUMP article
Loose or poor bracket alignmentCorrect or replace if necessary
Hissing When Parking
Internal leakage in steering gearCheck valved assembly first
Chirp in Steering Pump
Loose or worn power steering beltAdjust or replace if necessary
Buzzing When Not Steering
Noisy pumpSee POWER STEERING
PUMP article
Free play in steering shaft bearingSee STEERING COLUMN
article
Bearing loose on shaft serrationsSee STEERING COLUMN
article
Clicking Noise in Pump
Pump slippers too longSee POWER STEERING
PUMP article
Broken slipper springsSee POWER STEERING
PUMP article
Excessive wear or nicked rotorsSee POWER STEERING
PUMP article
Damaged cam contourSee POWER STEERING
PUMP article
Poor Return of Wheel
Wheel rubbing against turn signalSee STEERING COLUMN
SWITCHES article
Flange rubbing steering gear adjusterSee STEERING COLUMN
article
Tight or frozen steering shaft bearingSee STEERING COLUMN
article
Steering gear out of adjustmentSee POWER STEERING
GEAR article
Sticking or plugged spool valveSee POWER STEERING
PUMP article
Improper front end alignmentSee WHEEL ALIGNMENT
article
Wheel bearings worn or looseSee FRONT SUSPENSION
article
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Ties rods or ball joints bindingCheck and replace if necessary
Intermediate shaft joints bindingSee STEERING COLUMN
article
Kinked pressure hosesCorrect or replace if necessary
Loose housing head spanner nutSee POWER STEERING
GEAR article
Damaged valve leverSee POWER STEERING
GEAR article
Sector shaft adjusted too tightSee ADJUSTMENTS in
POWER STEERING GEAR
article
Worm thrust bearing adjusted too tightSee ADJUSTMENTS in
POWER STEERING GEAR
article
Reaction ring sticking in cylinderSee POWER STEERING
GEAR article
Reaction ring sticking in housing headSee POWER STEERING
GEAR article
Steering pump internal leakageSee POWER STEERING
PUMP article
Steering gear-to-column misalignmentSee STEERING COLUMN
article
Lack of lubrication in linkageService front suspension
Lack of lubrication in ball jointsService front suspension
Increased Effort When Turning Wheel Fast Foaming, Milky Power Steering Fluid, Low Fluid Level or Low Pressure
High internal pump leakageSee POWER STEERING
PUMP article
Power steering pump belt slippingAdjust or replace if necessary
Low fluid levelCheck and fill to proper level
Engine idle speed to lowAdjust to correct setting
Air in pump fluid systemSee POWER STEERING
PUMP article
Pump output lowSee POWER STEERING
PUMP article
Steering gear malfunctioningSee POWER STEERING
GEAR article
Wheel Surges or Jerks
Low fluid levelCheck and fill to proper level
Loose fan beltAdjust or replace if necessary
Insufficient pump pressureSee POWER STEERING
PUMP article
Sticky flow control valveSee POWER STEERING
PUMP article
Linkage hitting oil pan at full turnReplace bent components
Kick Back or Free Play
Air in pump fluid systemSee POWER STEERING
PUMP article
Worn poppet valve in steering gearSee POWER STEERING
PUMP article
Excessive over center lashSee POWER STEERING
GEAR article
Thrust bearing out of adjustmentSee POWER STEERING
GEAR article
Free play in pot couplingSee POWER STEERING
PUMP article
Steering gear coupling loose on shaftSee POWER STEERING
PUMP article
Steering disc mounting bolts looseTighten or replace if necessary
Coupling loose on worm shaftTighten or replace if necessary
Improper sector shaft adjustmentSee POWER STEERING
GEAR article
Excessive worm piston side playSee POWER STEERING
GEAR article
Damaged valve leverSee POWER STEERING
GEAR article
Universal joint looseTighten or replace if necessary
Defective rotary valveSee POWER STEERING
GEAR article
No Power When Parking
Sticking flow control valveSee POWER STEERING
PUMP article
Insufficient pump pressure outputSee POWER STEERING
PUMP article
Excessive internal pump leakageSee POWER STEERING
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STEERING COLUMN TROUBLE SHOOTING
BASIC STEERING COLUMN TROUBLE SHOOTING CHART
PUMP article
Excessive internal gear leakageSee POWER STEERING
PUMP article
Flange rubs against gear adjust plugSee STEERING COLUMN
article
Loose pump beltAdjust or replace if necessary
Low fluid levelCheck and add proper amount
of fluid
Engine idle too lowAdjust to correct setting
Steering gear-to-column misalignedSee STEERING COLUMN
article
No Power, Left Turn
Left turn reaction seal "O" ring wornSee POWER STEERING
GEAR article
Left turn reaction seal damaged/missingSee POWER STEERING
GEAR article
Cylinder head "O" ring damagedSee POWER STEERING
PUMP article
No Power, Right Turns
Column pot coupling bottomedSee STEERING COLUMN
article
Right turn reaction seal "O" ring wornSee POWER STEERING
GEAR article
Right turn reaction seal damagedSee POWER STEERING
GEAR article
Internal leakage through piston end plugSee POWER STEERING
GEAR article
Internal leakage through side plugsSee POWER STEERING
GEAR article
Lack of Effort in Turning
Left and/or right reaction seal sticking in cylinder headReplace, see POWER
STEERING GEAR article
Wanders to One Side
Front end alignment incorrectSee WHEEL ALIGNMENT
article
Unbalanced steering gear valveSee POWER STEERING
GEAR article
Low Pressure Due to Steering Pump
Flow control valve stuck or inoperativeSee POWER STEERING
PUMP article
Pressure plate not flat against cam ringSee POWER STEERING
PUMP article
Extreme wear of cam ringReplace and check
adjustments
Scored plate, thrust plate or rotorSee POWER STEERING
PUMP article
Vanes not installed properlySee POWER STEERING
PUMP article
Vanes sticking in rotor slotsSee POWER STEERING
PUMP article
Cracked/broken thrust or pressure plateSee POWER STEERING
PUMP article
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
Noise in Steering
Coupling pulled apartSee STEERING COLUMNS
article
Column not correctly alignedSee STEERING COLUMNS
article
Broken lower jointReplace joint
Horn contact ring notSee STEERING COLUMN
article
Bearing not lubricatedSee STEERING COLUMN
article
Shaft snap ring not properly seatedReseat or replace snap ring
Plastic spherical joint not lubricatedSee STEERING COLUMN
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Mismatched tiresSee WHEEL ALIGNMENT
Broken or sagging springSee SUSPENSION section
Broken torsion barSee SUSPENSION section
Power steering valve not centeredSee STEERING section
Front alignment out of toleranceSee WHEEL ALIGNMENT
section
Defective wheel bearingSee WHEEL BEARINGS in
SUSPENSION section
Uneven sway bar linksSee SUSPENSION section
Frame bentCheck for frame damage
Steering system bushing wornSee STEERING section
Hard Steering
Idler arm bushing too tightSee STEERING LINKAGE in
STEERING section
Ball joint tight or seizedSee SUSPENSION section
Steering linkage too tightSee STEERING LINKAGE in
STEERING section
Power steering fluid lowAdd proper amount of fluid
Power steering drive belt looseSee STEERING section
Power steering pump defectiveSee STEERING section
Steering gear out of adjustmentSee STEERING section
Incorrect wheel alignmentSee WHEEL ALIGNMENT
Damaged steering gearSee STEERING section
Damaged suspensionSee SUSPENSION section
Bent steering knuckle or supportsSee SUSPENSION section
Vehicle "Wanders"
Strut rod or control arm bushing wornSee SUSPENSION section
Loose or worn wheel bearingsSee WHEEL BEARINGS in
SUSPENSION section
Improper tire inflationCheck tire pressure
Stabilizer bar missing or defectiveSee SUSPENSION section
Wheel alignment out of toleranceSee Adjustment in WHEEL
ALIGNMENT section
Broken springSee SUSPENSION section
Defective shock absorberReplace shock absorbers
Worn steering & suspension componentsSee SUSPENSION section
Front End Shimmy
Tire out of balance/roundCheck tire balance
Excessive wheel runoutSee WHEEL ALIGNMENT
Insufficient or improper casterSee WHEEL ALIGNMENT
section
Worn suspension or steering componentsSee SUSPENSION section
Defective shock absorbersReplace shock absorber
Wheel bearings worn or looseSee WHEEL BEARING ADJ.
in SUSPENSION section
Power steering reaction Bracket looseSee STEERING section
Steering gear box (rack) mounting looseSee STEERING section
Steering gear adjustment looseSee STEERING section
Worn spherical jointsSee SUSPENSION section
Toe-In Not Adjustable
Lower control arm bentSee SUSPENSION section
Frame bentCheck frame for damage
Camber Not Adjustable
Control arm bentSee SUSPENSION section
Frame bentCheck frame for damage
Hub & bearing not seated properlySee SUSPENSION section
Copyr ight 2009 Mitchell Repair Information Company, LLC. All Rights Reserved.
Article GUID: A00027342
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Back To Article
GENERAL INFORMATION
T ROUBLE SHOOT ING
* PLEASE READ THIS FIRST *
ENGINE PERFORMANCE
TUNE-UP TROUBLE SHOOTING NOTE:T his article is generic in nature and all inform ation does not apply to all vehicles. For vehicle specific
inform ation, see the appropriate articles in the ENGINE PERFORMANCE category.
NOTE:T his article is generic in nature and all inform ation does not apply to all vehicles. For vehicle specific
inform ation, see the appropriate articles in the ENGINE PERFORMANCE category.
Problem & Possible CauseAction
Carbon Fouled Plugs
C l o gge d Air Fil t e rReplace Air Filter
Incorrect Idle SpeedReset Idle Speed
Faulty Ignition WiringReplace Ignition Wiring
Sticky Valves/Worn Valve SealCheck Valve Train
Fuel Injection OperationCheck Fuel Injection
Wet/Oil Fouled Plugs
Worn Rings/PistonsOverhaul/Replace Engine
Excessive Cylinder WearOverhaul/Replace Engine
Plug Gap Bridged
Combustion Chamber Carbon DepositsClean Combustion
Chamber
Blistered Electrode
Engine OverheatingCheck Cooling System
Loose Spark PlugsClean/Torque Plugs
Over-Advanced TimingReset Timing
Wrong Plug Heat RangeInstall Correct Plug
Melted Electrodes
Incorrect TimingReset Timing
Burned ValvesReplace Valves
Engine OverheatingCheck Cooling System
Wrong Plug Heat RangeInstall Correct Plug
Engine Won't Start
Loose ConnectionsCheck Connections
No PowerCheck Fuses/Battery
Loose/Worn Timing Belt/Chain/GearsCheck Belt/Chain/Gears
Engine Runs Rough
Leaky/Clogged Fuel InjectorsRepair Fuel Injectors
Leaky/Clogged Fuel LinesRepair Fuel Lines
Clogged Fuel FilterReplace Fuel Filter
Incorrect TimingReset Timing/Check
Advance
Faulty Plugs/WiresReplace Plugs/Wires
Uneven CompressionOverhaul/Replace Engine
Poor Acceleration
Incorrect Ignition TimingReset Timing
Leaky ValvesCheck Compression
Component Failure
Spark ArcingReplace Faulty Part
Defective Pick-Up CoilReplace Pick-Up Coil
Defective Ignition CoilReplace Ignition Coil
Defective Control UnitReplace Control Unit
Ignition Diagnosis By Scope Pattern
All Firing Lines Abnormally High
Retarded Ignition TimingReset Ignition Timing
Lean Air/Fuel MixtureAdjust Fuel Mixture
High Secondary ResistanceRepair Secondary
Ign it io n
All Firing Lines Abnormally Low
Rich Air/Fuel MixtureAdjust Air/Fuel Mixture
Arcing Coil WireReplace Coil Wire
Cracked CoilReplace Coil
Low Coil OutputReplace Coil
Low CompressionCheck/Repair Engine
Page 1 of 3 MITCHELL 1 ARTICLE - GENERAL INFORMATION TROUBLE SHOOTING
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Fig. 16: Cutaway View Of Typical Integrated Electronic EGR Valve

Courtesy of GENERAL MOTORS CORP.
SPARK CONTROLS (SPK)
Spark control systems are designed to ensure the air/fuel mixture is ignited at the best possible moment to provide optimum efficiency and
power and cleaner emissions.
Ensure vacuum hoses to the distributor, carburetor, spark delay valves, thermal vacuum switches, etc., are in place and routed properly. On
Computerized Engine Controls (CEC), check for presence of required sensors (O2, MAP, CTS, TPS, etc.). Ensure they have not been
tampered with or modified.
Check for visible modification or replacement of the feedback carburetor, fuel injection unit or injector(s) with a non-feedback carburetor or
fuel injection system. Check for modified emission-related components unacceptable for use on pollution-controlled vehicles.
AIR INJECTION SYSTEM (AIS)
Air Pump Injection System (AP)
The air pump is a belt-driven vane type pump, mounted to engine in combination with other accessories. The air pump itself consists of the
pump housing, an inner air cavity, a rotor and a vane assembly. As the vanes turn in the housing, filtered air is drawn in through the intake port
and pushed out through the exhaust port. See Fig. 17
.
Check for missing or disconnected belt, check valve(s), diverter valve(s), air distribution manifolds, etc. Check air injection system for proper
hose routing.
Page 10 of 12 MITCHELL 1 ARTICLE - EMISSION CONTROL VISUAL INSPECTION PROCEDURES 1983-93 GENERAL INFORMA...
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article. Drain oil from compressor through suction and discharge ports. Measure amount of oil drained. If amount drained is more than
2.4 ounces, fill with same amount using new oil. If amount drained is less than 2.4 ounces, fill with 2.4 ounces. Install compressor and
recharge.
3. If A/C components are replaced, add refrigerant oil to system. Add 1.4 ounces if condenser is replaced. Add 2 ounces if the evaporator
is replaced. Oil does not need to be added if receiver-drier is replaced.
SANDEN SCROLL DRAIN & REFILL
Discharge system. Remove compressor from vehicle. Drain oil from compressor through inlet and outlet holes. Refill compressor with 2.8
ounces of oil through suction port. When replacing condenser, add .5 ounce. When replacing evaporator, add 1.7 ounces. When replacing
other A/C components, add .5 ounce per component replaced.
SANDEN 5-CYL DRAIN & REFILL
1. Discharge system. Remove compressor belt and loosen mounting bolts. Rotate compressor in brackets until filler plug is at top. Clean
area around filler plug and remove plug slowly. Rotate front hub plate so notch in lobe is 110 degrees from the bottom. This rotates ball
end of top piston to align with oil fill port and allows clearance for dipstick. See Fig. 1
.
2. Insert compressor dipstick diagonally from right to left until stop on dipstick contacts filler plug surface. Remove dipstick and note oil
fill level. Each increment on dipstick represents one ounce of oil. Add oil if necessary to reach 3-4 ounce level.

Fig. 1: Sanden 5
-Cylinder Oil Level Checking
Courtesy of SANDEN INTERNATIONAL U.S.A, INC.
SANDEN 7-CYL DRAIN & REFILL
1. Before checking and adjusting oil level, operate compressor at engine idle speed, and set controls at maximum cooling and high blowing
speed for 20-30 minutes to return oil to compressor.
2. Stop engine. Discharge refrigerant and remove compressor from vehicle. See SERVICING PRECAUTIONS at the beginning of this
article. Remove oil drain plug and drain oil. Measure amount of oil drained. Install drain plug with new "O" ring.
3. If amount drained is more than 3 ounces, fill with same amount using new oil. If amount drained is less than 3 ounces, fill with 3
ounces. Install filler plug. Install compressor and recharge system.
Copyr ight 2009 Mitchell Repair Information Company, LLC. All Rights Reserved.
Article GUID: A00038952
Page 4 of 4 MITCHELL 1 ARTICLE - 1991 GENERAL SERVICING A/C Compressor Refrigerant Oil Checking
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5. Check blower motor fan switch continuity. Resistance should not exceed 4 ohms. See BLOWER MOTOR FAN SWITCH
CONTINUITY table. If continuity is not present, replace fan switch. If continuity is okay, repair open in Black wire from blower motor
switch to ground.
BLOWER MOTOR FAN SWITCH CONTINUITY
REMOVAL & INSTALLATION
CONTROL PANEL
1. Remove bezel screws and accessory bezel. Remove radio. Remove 4 screws securing control panel to instrument panel. Remove glove
box attaching screws and glove box. Remove the retaining clip and disconnect fresh/recirculation air door cable from mode door lever.
2. Disconnect mode select cable at mode control door lever. Disconnect temperature control cable at temperature control mode door lever.
Pull control panel away from instrument panel. Disconnect blower motor switch connector. Disconnect illumination electrical
connector. Remove control panel. To install, reverse removal procedure. Adjust control cables. See ADJUSTMENTS in this article.
BLOWER MOTOR FAN SWITCH
Remove control panel. See CONTROL PANEL R & I
. Remove blower motor fan switch knob. Remove attaching nut. To install, reverse
removal procedure.
HEATER CORE
1. Disconnect negative battery cable. Remove steering wheel by prying out center trim insert and removing steering wheel retaining nut.
Remove 2 steering wheel cover retaining screws and remove cover. Using a steering wheel puller, remove steering wheel.
2. Remove 5 screws and remove lower and upper steering column covers. Disconnect electrical connections and remove multifunction
switch. Remove 5 screws and pull instrument cluster hood rearward. Disconnect electrical connections and remove instrument cluster
hood.
3. Disconnect speedometer cable at transaxle. Remove 4 instrument cluster screws. Pull instrument cluster rearward and disconnect
speedometer cable and electrical connections. Remove instrument cluster.
4. Remove 2 center bracket mounting bolts under steering column and remove bracket. Remove glove box attaching screws and remove
glove box. Remove left and right heater ducts. Remove fuse panel cover. Remove 2 screws securing fuse panel and push fuse panel
inward. DO NOT remove fuse panel.
5. Slide both seats to most forward position. Remove 2 console attaching screws, located in front of seat belt anchors. Slide both seats to
rearmost position. Remove parking brake console insert. Using a Phillips screwdriver, remove push retainer insert, located at front lower
edge of parking brake console. Pull back on parking brake lever and remove parking brake console.
6. Remove gearshift knob. Remove screws and remove shift console. Remove radio/heater control panel bezel screws and remove bezel.
Remove 4 radio attaching screws. Pull radio out and disconnect antenna lead and electrical connections. Disconnect radio ground lead
and remove radio.
7. Remove 4 screws attaching heater control panel. Disconnect control cables and electrical connections. Remove control panel, while
pulling cables through opening.
8. Pry out bolt cover trim inserts in top corners of dash. Remove bolts located under trim panels. Remove 7 instrument panel attaching
bolts and 2 nuts. Pull instrument panel rearward. Disconnect any harness connectors and clips. Remove instrument panel.
9. Disconnect electrical connections at blower and resistor. Remove harness from routing brackets on heater box. Loosen clamp screw
securing air inlet housing. Remove attaching nuts at top and bottom of heater box. Disconnect defroster ducts and remove heater
assembly.
10. Disconnect link connecting 2 defroster doors. Remove attaching screw just above and to right of blower resistor. Turn heater assembly
around and remove screw just to left of blower motor opening. Remove clips securing 2 halves of heater assembly. Separate halves. Lift
out heater core.
11. To install, reverse removal procedure. Ensure all heater control cables are routed and adjusted properly. See ADJUSTMENTS in this
article. Fill cooling system. Check for leaks.
BLOWER MOTOR & RESISTOR
Disconnect negative battery cable. Remove instrument panel spacer brace located below steering column. Remove airflow duct below steering
column. Disconnect blower motor or resistor wiring. Remove 3 blower motor attaching screws or 2 resistor attaching screws and remove
component. To install, reverse removal procedure.
Switch PositionContinuity Between Wire Colors
1Black-to-Blue/White
2Black-to-Blue/Yellow & Blue/Yellow-to-Blue/Red
3Black-to-Blue/Black & Blue/Black-to-Blue/Red
Page 2 of 4 MITCHELL 1 ARTICLE - HEATER SYSTEM 1990-92 HEATER SYSTEMS Ford Motor Co.
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