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.
1978 Mazda Cosmo Automatic TransFACTORY OEM SERVICE PROCEDURE
1976-78 Models (Except RX7 Man. Trans.)
- Disconnect vacuum tube from trailing vacuum control unit of distributor. Disconnect water temperature switch and connect a jumper wire to both connector terminals. See Figure.
- Start engine and set engine speed at 2000 RPM with choke knob. No vacuum should be felt at vacuum sensing tube. On Federal models, push choke knob in fully. Suction should now be felt at disconnected trailing vacuum tube. On California models, suction should be felt 104-156 seconds after starting engine.
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.
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