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 Honda Prelude Si, StandardFACTORY OEM SERVICE PROCEDURE
Hot Engine
- Ensure engine is at normal operating temperature. On Accord models, disconnect hose No. 14 from power valve control solenoid valve located within control box, and plug hose. See Fig 1 and Fig 2 .
- On Civic 1500 models, disconnect vacuum hose from power valve at carburetor and plug hose. See Figure . On Prelude models, disconnect hose No. 14 from control box No. 1 and plug hose. See Figure and Figure .
- On Civic 1500 models with manual transmission and without power steering, remove cover from control box No. 2. On all models, start engine and check that frequency solenoid valves A and B are operating while running engine at 2500 RPM.
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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