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 Chevrolet Spectrum ExpressFACTORY OEM SERVICE PROCEDURE
Mixture Control Valve
- Mixture Control Valve (MCV) is located under air cleaner cover. The MCV diaphragm chamber contains 2 sub-chambers "A" and "B". To check operation, remove air cleaner cover and element and start engine.
- Disconnect vacuum hose from MCV. Place a finger over air inlet of MCV. Vacuum should not be felt. Reconnect vacuum hose. Vacuum should be present. See Fig 1 .
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.