Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
1987 Ford Mustang L4-140 2.3L SOHCFACTORY OEM SERVICE PROCEDURE
Repair and Diagnosis
- A L L Diagnostic Trouble Codes ( DTC )
- Relays and Modules
- Relays and Modules - Body and Frame
- Relays and Modules - Cooling System
- Relays and Modules - Cruise Control
- Relays and Modules - Engine
- Relays and Modules - HVAC
- Relays and Modules - Instrument Panel
- Relays and Modules - Lighting and Horns
- Relays and Modules - Powertrain Management
- Relays and Modules - Starting and Charging
- Relays and Modules - Windows and Glass
- Relays and Modules - Wiper and Washer Systems
- Sensors and Switches
- Sensors and Switches - Accessories and Optional Equipment
- Sensors and Switches - Body and Frame
- Sensors and Switches - Brakes and Traction Control
- Sensors and Switches - Cooling System
- Sensors and Switches - Cruise Control
- Sensors and Switches - Engine
- Sensors and Switches - HVAC
- Sensors and Switches - Instrument Panel
- Sensors and Switches - Lighting and Horns
- Sensors and Switches - Powertrain Management
- Sensors and Switches - Computers and Control Systems
- Air Flow Meter/Sensor
- Barometric Pressure Sensor
- Barometric Pressure Switch
- Camshaft Position Sensor
- Coolant Temperature Sensor/Switch (For Computer)
- Crankshaft Position Sensor
- EGR Valve Position Sensor
- Air Temperature Sensor ( Ambient / Intake )
- Knock Sensor
- Manifold Pressure/Vacuum Sensor
- Oxygen Sensor
- Power Steering Pressure Switch
- Throttle Position Sensor
- Vehicle Speed Sensor
- Sensors and Switches - Emission Control Systems
- Sensors and Switches - Fuel Delivery and Air Induction
- Sensors and Switches - Ignition System
- Sensors and Switches - Computers and Control Systems
- Sensors and Switches - Restraints and Safety Systems
- Sensors and Switches - Starting and Charging
- Sensors and Switches - Steering and Suspension
- Sensors and Switches - Windows and Glass
- Sensors and Switches - Wiper and Washer Systems
- Maintenance
- Alignment
- Tune-up and Engine Performance Checks
- Timing Belt
- Timing Component Alignment Marks
- Drive Belt
- Filters
- Hoses
- Fluids
- Brake Bleeding
- Fuses and Circuit Breakers
- Service Reminder Indicators
- Wheels and Tires
- Service Intervals
- Severe Service Defined
- Routine Service
- Normal Service
- 7500 MI or 12000 KM
- 15000 MI or 24000 KM
- 22500 MI or 36000 KM
- 30000 MI or 48000 KM
- 37500 MI or 60000 KM
- 45000 MI or 72000 KM
- 52500 MI or 84000 KM
- 60000 MI or 96000 KM
- 67500 MI or 108000 KM
- 75000 MI or 120000 KM
- 82500 MI or 132000 KM
- 90000 MI or 144000 KM
- 97500 MI or 156000 KM
- 105000 MI or 168000 KM
- 112500 MI or 180000 KM
- 120000 MI or 192000 KM
- Severe Service
- 3000 MI or 4800 KM
- 6000 MI or 9600 KM
- 9000 MI or 14400 KM
- 12000 MI or 19200 KM
- 15000 MI or 24000 KM
- 18000 MI or 28800 KM
- 21000 MI or 33600 KM
- 24000 MI or 38400 KM
- 27000 MI or 43200 KM
- 30000 MI or 48000 KM
- 33000 MI or 52800 KM
- 36000 MI or 57600 KM
- 39000 MI or 62400 KM
- 42000 MI or 67200 KM
- 45000 MI or 72000 KM
- 48000 MI or 76800 KM
- 51000 MI or 81600 KM
- 54000 MI or 86400 KM
- 57000 MI or 91200 KM
- 60000 MI or 96000 KM
- 63000 MI or 100800 KM
- 66000 MI or 105600 KM
- 69000 MI or 110400 KM
- 72000 MI or 115200 KM
- 75000 MI or 120000 KM
- 78000 MI or 124800 KM
- 81000 MI or 129600 KM
- 84000 MI or 134400 KM
- 87000 MI or 139200 KM
- 90000 MI or 144000 KM
- 93000 MI or 148800 KM
- 96000 MI or 153600 KM
- 99000 MI or 158400 KM
- 102000 MI or 163200 KM
- 105000 MI or 168000 KM
- 108000 MI or 172800 KM
- 111000 MI or 177600 KM
- 114000 MI or 182400 KM
- 117000 MI or 187200 KM
- 120000 MI or 192000 KM
- 150000 MI or 240000 KM
Service and Repair
Technical Service Bulletins
- Engine, Cooling and Exhaust
- Engine
- Camshaft, Lifters and Push Rods
- Cylinder Block Assembly
- Cylinder Head Assembly
- Drive Belts, Mounts, Brackets and Accessories
- Engine Lubrication
- Intake Manifold
- Lamps and Indicators - Engine
- Relays and Modules - Engine
- Seals and Gaskets
- Sensors and Switches - Engine
- Timing Components
- Tune-up and Engine Performance Checks
- Water Pump
- Application and ID
- Service and Repair
Specifications- Technical Service Bulletins
- Cooling System
- Coolant
- Coolant Level Sensor
- Radiator Cooling Fan
- Engine - Coolant Temperature Sensor/Switch
- Heater Core
- Lamps and Indicators - Cooling System
- Radiator Cap
- Relays and Modules - Cooling System
- Sensors and Switches - Cooling System
- Temperature Gauge
- Temperature Warning Lamp/Indicator
- Thermostat
- Water Pump
Locations
Diagrams- Specifications
- Technical Service Bulletins
- Exhaust System
- Engine
- Powertrain Management
- Relays and Modules - Powertrain Management
- Sensors and Switches - Powertrain Management
- Sensors and Switches - Computers and Control Systems
- Air Flow Meter/Sensor
- Barometric Pressure Sensor
- Barometric Pressure Switch
- Camshaft Position Sensor
- Coolant Temperature Sensor/Switch (For Computer)
- Crankshaft Position Sensor
- EGR Valve Position Sensor
- Air Temperature Sensor ( Ambient / Intake )
- Knock Sensor
- Manifold Pressure/Vacuum Sensor
- Oxygen Sensor
- Power Steering Pressure Switch
- Throttle Position Sensor
- Vehicle Speed Sensor
- Sensors and Switches - Emission Control Systems
- Sensors and Switches - Fuel Delivery and Air Induction
- Sensors and Switches - Ignition System
- Sensors and Switches - Computers and Control Systems
- Tune-up and Engine Performance Checks
- Computers and Control Systems
- Air Flow Meter/Sensor
- Air Temperature Sensor ( Ambient / Intake )
- Barometric Pressure Sensor
- Barometric Pressure Switch
- Camshaft Position Sensor
- Coolant Temperature Sensor/Switch (For Computer)
- Crankshaft Position Sensor
- EGR Valve Position Sensor
- Engine Control Module
- Feedback Control Solenoid
- Idle Speed/Throttle Actuator - Electronic
- Idle Speed/Throttle Actuator - Mechanical
- Knock Sensor
- Main Relay (Computer/Fuel System)
- Malfunction Indicator Lamp
- Manifold Pressure/Vacuum Sensor
- Oxygen Sensor
- Power Steering Pressure Switch
- Relays and Modules - Computers and Control Systems
- Sensors and Switches - Computers and Control Systems
- Air Flow Meter/Sensor
- Barometric Pressure Sensor
- Barometric Pressure Switch
- Camshaft Position Sensor
- Coolant Temperature Sensor/Switch (For Computer)
- Crankshaft Position Sensor
- EGR Valve Position Sensor
- Air Temperature Sensor ( Ambient / Intake )
- Knock Sensor
- Manifold Pressure/Vacuum Sensor
- Oxygen Sensor
- Power Steering Pressure Switch
- Throttle Position Sensor
- Vehicle Speed Sensor
- Throttle Position Sensor
- Vehicle Speed Sensor
Service Precautions
Description and Operation
Testing and Inspection- Initial Inspection and Diagnostic Overview
- Reading and Clearing Diagnostic Trouble Codes
- Reading Diagnostic Trouble Codes
- Quick Test Appendix (Detailed Testing Instructions)
- Quick Tests
- 1.0 - Visual Check & Vehicle Preparation
- 2.0 - Equipment Hook-Up
- 3.0A - Performing the Key On Engine Off Self-Test
- 3.0B - Key-On, Engine-Off Self-Test (Codes)
- 3.0C - Passenger Car Service Code Chart (KOEO)
- 4.0 - Computed Timing Check
- 5.0A - Engine Running Self-Test - Code Output
- 5.0B - Engine Running Self-Test (Codes)
- 5.0C - Service Code Chart
- 6.0 - Continuous Self-Test
- Clearing Diagnostic Trouble Codes
- Reading Diagnostic Trouble Codes
- Diagnostic Trouble Code Tests and Associated Procedures
- Symptom Related Diagnostic Procedures
- Diagnostic Routines
- 201 - Cranks Normally But Won't Start
- 202 - Starts Normally But Won't Run (Stalls)
- 203 - Cranks Normally But Slow to Start
- 205 - Misses Under Load
- 207 - Hesitates or Stalls On Acceleration
- 208 - Backfire (Induction or Exhaust)
- 209 - Lack of Power
- 210 - Surge At Steady Speed
- 211 - Engine Diesels (or Idles Too Fast)
- 212 - Engine Noise
- 213 - Poor Fuel Economy
- 214 - High Oil Consumption
- 215 - Spark Knock/Pinging
- 216 - Engine Vibrates At Normal Speeds
- 217 - Engine Runs Cold
- 218 - Engine Runs Hot
- 219 - Exhaust Smoke
- 220 - Gas Smell
- 221 - Check Engine Light Always On or Never On
- Symptom Charts
- Diagnostic Routines
- Pinpoint Tests
- A - No Start Test
- B - Vehicle Battery
- C - Reference Voltage
- DA - Vane Air Temperature Sensor (VAT)
- DB - Air Charge Temperature Sensor (ACT)
- DD - EGR Valve Position Sensor (EVP) Control/Vent (EGRC/EGRV)
- DE - Engine Coolant Temperature Sensor (ECT)
- DF - Manifold Absolute Pressure (MAP)/Barometric Pressure (BP)
- DG - Knock Sensor
- DH - Throttle Position (TP) Sensor
- DK - Vane Air Flow Sensor (VAF)
- DL - Pressure Feedback EGR (PFE) & EGR Valve Regulator (EVR)
- DP - Vehicle Speed Sensor (VSS)
- FA - Neutral Drive Switch A/C Input
- FC - Vehicle (Key) Power
- FD - Brake On/Off (BOO) Switch
- FF - Power Steering Pressure Switch (PSPS)
- HE - Fuel Control
- J - Fuel Pump Circuit
- KA - EGR On/Off Control
- KC - Air Management System
- KD - Canister Purge (CANP) Solenoid
- KE - Idle Speed Control
- KL - Shift Indicator Light (SIL)
- KM - WOT A/C Cut-Off (WAC) A/C Demand
- KN - Turbo Boost
- KP - Exhaust Heat Control
- KR - Converter Clutch Override (CCO)
- KS - Converter Clutch Override & Shift Solenoid 3/4-4/3
- M - Dynamic Response Test
- ML - "Check Engine" Lamp (Malfunction Indicator Lamp)
- N - Ignition Diagnostic Monitor (IDM)
- P - Spark Timing Check
- Q - No Codes/Codes Not Listed
- S - System Check
- T - Transmission - AXOD
- X - Integrated Relay Control Module
- Y - Erratic Ignition
- Locations
- Diagrams
- Technical Service Bulletins
Tools and Equipment
- Emission Control Systems
- Air Injection
- Air Injection Vacuum Control Solenoid Valve
- Air Diverter Solenoid
- Air Diverter Valve
- Air Injection Bypass Valve
- Air Injection Check Valve
- Air Injection Control Valve
- Air Injection Filter
- Air Injection Hose/Tube
- Air Injection Manifold
- Air Injection Pump
- Air Injection Relief Valve
- Pulsed Secondary Air Injection
- Thermal Vacuum Valve
- Testing and Inspection
- Technical Service Bulletins
- Catalytic Converter
- Evaporative Emissions System
- Exhaust Gas Recirculation
- Positive Crankcase Ventilation
- Sensors and Switches - Emission Control Systems
- Thermostatic Air Cleaner
- Vacuum Restrictor
- Application and ID
- Description and Operation
- Testing and Inspection
- Diagrams
- Technical Service Bulletins
- Air Injection
- Fuel Delivery and Air Induction
- Fuel Pressure
- Fuel Pressure Release
- Idle Speed
- Air Cleaner Housing
- Air Flow Meter/Sensor
- Carburetor
- Fuel
- Fuel Filter
- Fuel Injector
- Fuel Line Coupler
- Fuel Pressure Regulator
- Fuel Pressure Test Port
- Fuel Pump
- Fuel Rail
- Fuel Return Line
- Fuel Supply Line
- Fuel Tank
- Idle Speed/Throttle Actuator - Electronic
- Idle Speed/Throttle Actuator - Mechanical
- Idle/Altitude Compensator (Non Comp. Controlled)
- Inertia Fuel Shutoff Switch
- Main Relay (Computer/Fuel System)
- Relays and Modules - Fuel Delivery and Air Induction
- Sensors and Switches - Fuel Delivery and Air Induction
- Throttle Body
- Throttle Position Sensor
- Service Precautions
- Application and ID
- Description and Operation
- Service and Repair
- Diagrams
- Technical Service Bulletins
- Ignition System
- Firing Order
- Ignition Timing
- Camshaft Position Sensor
- Crankshaft Position Sensor
- Distributor
- Hall Effect Sensor
- Ignition Cable
- Ignition Coil
- Ignition Control Module
- Ignition Timing Connector
- Knock Sensor
- Pick-Up Coil
- Relays and Modules - Ignition System
- Sensors and Switches - Ignition System
- Spark Plug
- Vacuum Restrictor
- Service Precautions
- Description and Operation
- Testing and Inspection
- Flow of Diagnosis
- Component Tests and General Diagnostics
- Intermittent Diagnostic Procedures
- Primary Circuit Tests
- Test 1, Ignition Coil Secondary Voltage (Crank Mode)
- Test 2, Ignition Coil Secondary Voltage (Run Mode)
- Test 3, Wiring Harness
- Test 4 & 5, Stator
- Test 6, TFI Module
- Test 7, Ignition Coil Primary Resistance
- Test 8, Ignition Coil Secondary Resistance
- Test 9, EEC-IV -- TFI-IV
- Test 10, Ignition Coil Supply Voltage
- Test 11, Wiring Harness
- Secondary Circuit Tests
- Diagrams
- Specifications
- Technical Service Bulletins
- Tools and Equipment
- Transmission Control Systems
- Application and ID
- Diagrams
- Technical Service Bulletins
- Transmission and Drivetrain
- Actuators and Solenoids - Transmission and Drivetrain
- Automatic Transmission/Transaxle
- Actuators and Solenoids - A/T
- Band
- Band Apply Servo
- Case
- Clutch
- Extension Housing
- Fluid - A/T
- Fluid Line/Hose
- Fluid Pump
- Governor
- Overdrive Assembly
- Seals and Gaskets
- Shifter A/T
- Shift Linkage
- Shift Modulator
- Throttle Valve Cable/Linkage
- Torque Converter
- Torque Converter Clutch Solenoid
- Transmission Cooler
- Valve Body
- Service and Repair
- Diagrams
- Specifications
- Technical Service Bulletins
- Clutch
- Differential Assembly
- Drive Axles, Bearings and Joints
- Drive/Propeller Shafts, Bearings and Joints
- Flywheel
- Manual Transmission/Transaxle
- Transmission Control Systems
- Technical Service Bulletins
- Tools and Equipment
- Brakes and Traction Control
- Starting and Charging
- Sensors and Switches - Starting and Charging
- Relays and Modules - Starting and Charging
- Battery
- Charging System
- Starting System
- Power and Ground Distribution
- Technical Service Bulletins
- Power and Ground Distribution
- Steering and Suspension
- Alignment
- Sensors and Switches - Steering and Suspension
- Steering
- Suspension
- Wheels and Tires
- Technical Service Bulletins
- Heating and Air Conditioning
- Accumulator HVAC
- Air Door
- Blower Motor
- Blower Motor Resistor
- Blower Motor Switch
- Compressor HVAC
- Condenser HVAC
- Control Assembly
- Control Module HVAC
- Coupler HVAC
- Evaporator Case
- Evaporator Core
- Expansion Block/Orifice Tube
- Heater Core
- Receiver Dryer
- Refrigerant
- Refrigerant Filter
- Refrigerant Oil
- Refrigerant Pressure Sensor / Switch
- Relays and Modules - HVAC
- Sensors and Switches - HVAC
- Vacuum Reservoir HVAC
- Service Precautions
- Testing and Inspection
- Service and Repair
- Retrofitting
- A/C System Flushing
- Evacuation
- Evacuation and Charging
- Leak Detection
- Oil Charge
- Oil Level Check
- Refrigerant Recovery
- System Check
- System Pressure Readings
- Diagrams
- Specifications
- Technical Service Bulletins
- Restraints and Safety Systems
- Accessories and Optional Equipment
- Body and Frame
- Bumper
- Doors, Hood and Trunk
- Exterior Moulding / Trim
- Fender
- Frame
- Interior Moulding / Trim
- Locks
- Mirrors
- Paint, Striping and Decals
- Relays and Modules - Body and Frame
- Roof and Associated Components
- Seats
- Sensors and Switches - Body and Frame
- Weatherstrip
- Technical Service Bulletins
- Cruise Control
- Brake Switch (Cruise Control)
- Clutch Switch
- Cruise Control Brush Assembly
- Cruise Control Module
- Cruise Control Servo
- Cruise Control Servo Cable
- Cruise Control Switch
- Cruise Control Vacuum Vent Solenoid
- Relays and Modules - Cruise Control
- Sensors and Switches - Cruise Control
- Vacuum Vent Valve
- Vehicle Speed Sensor/Transducer - Cruise Control
- Description and Operation
- Testing and Inspection
Adjustments- Diagrams
- Technical Service Bulletins
- Instrument Panel, Gauges and Warning Indicators
- Ammeter Gauge
- Audible Warning Device
- Charge Lamp/Indicator
- Cigarette Lighter
- Clock
- Coolant Level Indicator Module
- Dashboard / Instrument Panel
- Driver/Vehicle Information Display
- Fuel Gauge
- Fuel Gauge Sender
- Instrument Cluster / Carrier
- Key Reminder Switch
- Low Fuel Lamp/Indicator
- Malfunction Indicator Lamp
- Odometer
- Oil Level Warning Indicator
- Oil Level Warning Indicator Relay
- Oil Pressure Gauge
- Oil Pressure Sender
- Oil Pressure Warning Lamp/Indicator
- Parking Brake Warning Switch
- Relays and Modules - Instrument Panel
- Sensors and Switches - Instrument Panel
- Speedometer Cable
- Speedometer Head
- Speedometer Module
- Temperature Gauge
- Temperature Sensor (Gauge)
- Temperature Warning Lamp/Indicator
- Vacuum Gauge/Economy Meter
- Volt Meter Gauge
- Description and Operation
- Testing and Inspection
- Diagrams
- Technical Service Bulletins
- Lighting and Horns
- Windows and Glass
- Wiper and Washer Systems
- Relays and Modules - Wiper and Washer Systems
- Sensors and Switches - Wiper and Washer Systems
- Washer Fluid Level Indicator
- Washer Fluid Level Switch
- Windshield Washer Motor
- Windshield Washer Pump
- Windshield Washer Relay
- Windshield Washer Switch
- Wiper Control Module
- Wiper Gear Box
- Wiper Motor
- Wiper Motor Timer
- Wiper Relay
- Wiper Switch
- Description and Operation
- Testing and Inspection
- Locations
- Diagrams
- Technical Service Bulletins
- Application and ID
- Locations
- Diagrams
- Diagram Information and Instructions
- Connector Views
- Electrical Diagrams
- Power and Ground Distribution
- Charging System
- Convertible Top
- Cooling System
- Cruise Control
- Fuel Door
- Heated Glass Element
- Heating and Air Conditioning
- Instrument Panel, Gauges and Warning Indicators
- Lighting and Horns
- Mirrors
- Power Locks
- Power Trunk / Liftgate Lock Switch
- Power Window Circuit Breaker
- Power Window Motor
- Power Window Relay
- Power Window Switch
- Powertrain Management
- Radio/Stereo
- Seats
- Starting System
- Trunk / Liftgate Motor
- Trunk / Liftgate Relay
- Trunk / Liftgate Solenoid
- Trunk / Liftgate Switch
- Wiper and Washer Systems
- Fluid Diagrams
- Vacuum and Vapor Hose Diagrams
- Connectors
- Grounds
- Splices
- Specifications
- Electrical Specifications
- Air Flow Meter/Sensor
- Air Temperature Sensor ( Ambient / Intake )
- Alternator
- Barometric Pressure Sensor
- Battery
- Blower Motor
- Coolant Temperature Sensor/Switch (For Computer)
- Idle Speed/Throttle Actuator - Electronic
- Ignition System
- Manifold Pressure/Vacuum Sensor
- Starter Motor
- Throttle Position Sensor
- Vehicle Speed Sensor
- Voltage Regulator
- Mechanical Specifications
- Alignment
- Automatic Transmission/Transaxle
- Brake Caliper
- Brake Drum
- Brake Master Cylinder
- Brake Rotor/Disc
- Compressor Clutch
- Differential Assembly
- Engine
- Exhaust Manifold
- Flywheel
- Fuel Injector
- Idle Speed
- Manual Transmission/Transaxle
- Radiator Cooling Fan Temperature Sensor / Switch
- Spark Plug
- Wheel Cylinder
- Wheel Stud / Lug Nut
- Pressure, Vacuum and Temperature Specifications
- Capacity Specifications
- Fluid Type Specifications
- Electrical Specifications
- Technical Service Bulletins
Diagnostic Trouble Codes
Factory Service Tools
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.
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