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 Mitsubishi Starion ESI-RFACTORY OEM SERVICE PROCEDURE
High Altitude COMPENSATOR (HAC): California
- Disconnect White-striped vacuum hose from HAC. Connect vacuum pump to HAC. At low altitude, 3900 ft. (1200 m) or less, when vacuum is applied, vacuum should leak. At high altitude, vacuum should hold.
- On low altitude models, disconnect Black hose from HAC and connect vacuum pump. Vacuum should hold when applied. On high altitude models, disconnect Black hose from HAC and connect another vacuum pump (HAC now has 2 vacuum pumps connected to it). Hold vacuum with first pump, and apply vacuum with second pump. Vacuum should leak when applied.
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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