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.
1980 Plymouth Horizon Base, Automatic TransFACTORY OEM SERVICE PROCEDURE
Repair and Diagnosis
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Quick Lookups
Common Specs & Procedures
Electrical Component Locations
Technical Bulletins
Tire Fitment
Wiring Diagrams
- Using lemon2025'S System Wiring Diagrams
- Wiring Diagrams - Horizon & Omni
- Wiring Diagrams - Key & Seat Belt Warning Systems
- Wiring Diagrams - Oxygen Sensor Feedback System
- Wiring Diagrams - Spark Timing Systems - Electronic
- Wiring Diagrams - Speed Control Systems - Electric
- Wiring Diagrams - Wiper/Washer Systems
- Accessories & Equipment
- Body & Frame
- Brakes
- Drivelines & Axles
- Electrical
- Body Electrical
- Defoggers - Rear Window
- Door & Tailgate Locks
- Power Seats
- Power Windows
- Rear Window Defogger Fan - All Models
- Seat Belt & Key Warning Systems
- Speed Control Systems - Automatic
- Sun & Moon Roofs - Electric
- Switches, Gauges & Instrument Panels
- Wiper/Washer Systems - Concealed
- Wiper/Washer Systems - Liftgate
- Wiper/Washer Systems - Non-Concealed
- Charging Systems
- Component Locations
- Fuses & Circuit Breakers
- Switches, Gauges & Instrument Panels
- Horns
- Motors, Switches, Relays
- Defoggers - Rear Window
- Door & Tailgate Locks
- Power Seats
- Power Windows
- Rear Window Defogger Fan - All Models
- Seat Belt & Key Warning Systems
- Speed Control Systems - Automatic
- Sun & Moon Roofs - Electric
- Switches, Gauges & Instrument Panels
- Wiper/Washer Systems - Concealed
- Wiper/Washer Systems - Liftgate
- Wiper/Washer Systems - Non-Concealed
- Starters - BOSCH & NIPPONDENSO
- Wiring Diagrams
- Using lemon2025'S System Wiring Diagrams
- Wiring Diagrams - Horizon & Omni
- Wiring Diagrams - Key & Seat Belt Warning Systems
- Wiring Diagrams - Oxygen Sensor Feedback System
- Wiring Diagrams - Spark Timing Systems - Electronic
- Wiring Diagrams - Speed Control Systems - Electric
- Wiring Diagrams - Wiper/Washer Systems
- Body Electrical
- Engine Mechanical
- Engine Performance
- Emissions
- Engine Control Systems
- Air Injection Systems
- Catalytic Converters
- Computerized Engine Controls
- Electronic Feedback Carburetor
- Electronic Spark Control System
- Emission & Tune-Up Standards
- Emission Control Application
- Evaporation Control System
- Exhaust Gas RECIRCULATION
- Full Electric Choke System
- Orifice Spark Advance Control
- Positive Crankcase Ventilation System (PCV)
- Thermostatic Air Cleaners -- All Models
- Vacuum Diagrams
- Fuel Delivery
- Ignition System
- Tune-Up
- Vacuum Diagrams
- Wiring Diagrams
- General Information
- Abbreviations
- Basic Trouble Shooting
- Basic Trouble Shooting - General Information
- Brake System Trouble Shooting
- Commonly Used Abbreviations - General Information
- Cooling System Trouble Shooting
- Emission Control Abbreviations
- Engine Performance - Trouble Shooting - General Information
- Gasoline Engine Trouble Shooting
- General Servicing
- Manual & Power Steering Gear Trouble Shooting
- Manual A/C Systems - Trouble Shooting & Diagnosis
- Steering Column Trouble Shooting
- Suspension Trouble Shooting
- Wheel Alignment (Troubleshooting)
- Brakes
- Check Lists
- Driveline/Axles
- Electrical
- Engine
- Engine Performance
- Electrostatic Discharge Warning - General Information
- Engine Performance Diagnostic Routine Outline - General Information
- Engine Performance Safety Precautions
- Map - Engine Performance & Maintenance
- Parasitic Load Explanation & Test Procedures - General Information
- State Emission Standards - Diesel
- State Emission Standards - Gas
- Waveforms - Injector Pattern Tutorial - General Information
- Map - Exhaust Systems
- Heating, Ventilation & A/C (HVAC)
- Hoist/Jack
- Identification
- Metric Conversions
- Maintenance Reminder Light (Reset Procedures)
- Specifications Index
- Steering
- Towing Procedure
- Trouble Shooting - Manual Transmission - General Information
- Heating, Ventilation & A/C (HVAC)
- Maintenance
- Restraints
- Steering
- Suspension
- Transmission
- External Pages
Factory Service Tools
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- β’ You smell fuel, burning insulation, or see smoke.
- β’ Brakes feel soft, pull hard to one side, or make grinding noises.
- β’ The engine overheats, stalls repeatedly, or misfires under load.
- β’ You are missing required tools, torque specs, or safe lifting equipment.
- β’ You are not confident in the next step or safety outcome.
