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.
1983 Mercury Capri Base, AutomaticFACTORY OEM SERVICE PROCEDURE
Normally Closed Valve
- With engine at normal operating temperature, parking brake applied and transmission in "P" or "N," disconnect hoses from ports "A" and "B." See Figure Disconnect and plug line to port "D." With engine at 1500 RPM, air should flow from bypass vents.
- Reconnect line to port "D" and disconnect and plug line to port "S". Ensure vacuum is present in line to port "D." With engine at 1500 RPM, air should flow from port "B," and no air should flow from port "A".
- Apply 8-10 in. Hg vacuum to port "S." With engine at 1500 RPM, air should flow from port "A." If the valve has a vacuum bleed, some lesser amount of air will flow from port "A" or "B" and main discharge will change when vacuum is applied to port "S".
- If valve fails any test, replace valve. Reconnect hoses.
Factory Service Tools
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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.