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.
1991 Ford Probe GL, AutomaticFACTORY OEM SERVICE PROCEDURE
Amperage Output Test
- Connect ammeter in series with positive battery cable. Connect voltmeter negative lead to negative battery post and positive lead to positive battery post.
- Turn on all electrical accessories. Start engine and accelerate to 2500-3000 RPM. If alternator amperage output is within 10% of rated output, alternator is functioning properly. If correct output is not achieved, proceed to VOLTAGE OUTPUT TEST.
NOTE:
See ALTERNATOR SPECIFICATIONS table for rated output of alternator being tested.
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.