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.
Cold Temp. Activated Vacuum System: Description
The Cold Temperature Activated Vacuum (CTAV) System is designed to select either carburetor spark port vacuum or carburetor EGR port vacuum as a function of ambient air temperature. The selected vacuum source is used to control distributor vacuum advance unit. System consists of an ambient temperature switch, a three-way vacuum valve, an external vacuum bleed and a latching relay.
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.