1986 Oldsmobile Cutlass Ciera Repair Manual

The 1986 Oldsmobile Cutlass Ciera is a mid-size front-wheel drive vehicle featuring a 2.5L Tech IV four-cylinder engine or optional 3.0L and 3.8L V6 engines, three-speed automatic transmission, power steering, front disc/rear drum brakes, and comprehensive electronic systems. This manual covers maintenance procedures, troubleshooting, component replacement, and service specifications for DIY repairs and professional mechanics.

1. Vehicle Specifications 2. Maintenance Schedule 3. Engine Systems 4. Transmission & Drivetrain 5. Braking System 6. Electrical System 7. Suspension & Steering 8. Fuel System 9. Cooling System 10. Exhaust System 11. Troubleshooting Guide

Vehicle Specifications

Technical specifications for the 1986 Oldsmobile Cutlass Ciera models.

Specification	Details
Engine Options	2.5L Tech IV I4, 3.0L V6, 3.8L V6
Transmission	3-speed automatic (TH-125C)
Drivetrain	Front-wheel drive
Fuel System	Electronic fuel injection (EFI)
Brake System	Front disc, rear drum
Wheelbase	104.9 inches
Curb Weight	2,800-3,100 lbs
Fuel Capacity	15.2 gallons
Oil Capacity	4 quarts (with filter)
Coolant Capacity	12.5 quarts

Maintenance Schedule

Recommended service intervals for optimal vehicle performance.

Oil and filter change: Every 3,000 miles or 3 months
Tire rotation: Every 6,000 miles
Air filter replacement: Every 15,000 miles
Spark plugs: Every 30,000 miles
Coolant flush: Every 30,000 miles or 2 years
Transmission fluid: Every 30,000 miles
Brake fluid: Every 2 years
Timing belt: Every 60,000 miles (if equipped)

WARNING! Always use jack stands when working under vehicle. Never rely solely on hydraulic jack.

Engine Systems

Service procedures for engine components and systems.

Spark plug replacement: Gap 0.045 inches for 2.5L, 0.060 inches for V6
Valve adjustment: Hydraulic lifters - no adjustment required
Ignition timing: 10° BTDC for 2.5L, 15° BTDC for V6 engines
Compression test: Should be 140-160 psi, variation less than 20 psi
Oil pressure: 35-45 psi at 2000 RPM when warm
Belt tension: 1/2 inch deflection on longest span

CAUTION! Allow engine to cool before removing radiator cap to prevent burns.

Transmission & Drivetrain

Transmission Type: TH-125C 3-speed automatic
Fluid Type: Dexron II automatic transmission fluid
Fluid Capacity: 7.5 quarts (dry fill)
Shift Points: 1-2: 15 mph, 2-3: 25 mph at light throttle
CV Joints: Inspect boots every 15,000 miles
Differential: Integrated with transaxle
Transmission Mounts: Check for deterioration every 30,000 miles

Braking System

Brake service procedures and specifications.

Front Brakes: Disc brakes with single piston calipers, rotor thickness 0.940 inch minimum.

Rear Brakes: Drum brakes with self-adjusting mechanism, drum diameter 9.5 inches.

Brake Pad Replacement: Remove caliper bolts, compress piston, install new pads. Brake Shoe Replacement: Remove drum, disconnect springs, replace shoes and hardware. Master Cylinder: Bench bleed before installation. Brake Bleeding: Start with wheel farthest from master cylinder.

Electrical System

Battery, charging, and electrical component service.

Battery: 12V, 550 CCA, clean terminals monthly
Alternator: 65-85 amp output, check belt tension
Starter: 1.4 kW, check solenoid connections
Fuses: 10-30 amp blade-type fuses in dashboard panel
Lighting: Headlight adjustment screws behind bezel
Ignition System: HEI distributor, check cap and rotor

Tip: Disconnect battery negative terminal before electrical work to prevent shorts.

Suspension & Steering

Front struts and rear coil spring suspension maintenance.

Strut Replacement: Support vehicle, remove wheel, disconnect brake line bracket
Ball Joints: Check for play with pry bar
Tie Rod Ends: Replace if steering play exceeds 1/4 inch
Wheel Alignment: Camber -0.5° to +0.5°, Toe 0° to +0.20°
Power Steering: Use Dexron II fluid, check for leaks at rack
Stabilizer Links: Replace if bushings are cracked or worn

WARNING! Use proper spring compressor when working with struts or coil springs.

Fuel System

Fuel injection system service and maintenance.

Fuel Pump: Electric in-tank type, 13-15 psi pressure. Fuel Filter: Replace every 15,000 miles. Injectors: Bosch design, check for clogging with fuel pressure test. Throttle Body: Clean with appropriate cleaner every 30,000 miles. Fuel Pressure Regulator: Maintains 9-13 psi system pressure.

Cooling System

Radiator, thermostat, and cooling component service.

Radiator: Aluminum core with plastic tanks. Thermostat: 195°F opening temperature. Water Pump: Gear-driven from timing chain. Coolant: 50/50 ethylene glycol and water mixture. Hoses: Replace if soft, cracked, or swollen. Pressure Cap: 15 psi rating - test annually.

Exhaust System

Exhaust system inspection and component replacement.

Manifold: Cast iron, check for cracks. Catalytic Converter: Federal emissions standard. Muffler: Transverse mounted behind rear axle. Pipe Diameter: 2.0 inches. Hangers: Rubber isolated, replace if deteriorated. Oxygen Sensor: Single wire, replace every 60,000 miles.

Troubleshooting Guide

Symptom	Possible Cause	Corrective Action
Engine won't start	Fuel pump, ignition, battery	Check fuel pressure, spark, battery voltage
Rough idle	Vacuum leak, dirty injectors	Inspect vacuum hoses, clean throttle body
Overheating	Thermostat, water pump, radiator	Test thermostat, check coolant flow
Brake pulsation	Warped rotors	Resurface or replace front rotors
Transmission slippage	Low fluid, worn bands	Check fluid level and condition
Electrical issues	Alternator, grounds	Test charging system, clean battery grounds

Technical Support: Contact GM technical assistance at 1-800-GM-HELP

Parts: Genuine GM parts available through authorized dealers