Alternator Output

[Quickslick4444]

Whats the output voltage on a 88' tiva alternator.

[WmWatt]

The voltage across the battery terminals with the engine idling should be 14.7 volts according to my Haynes manual, but advice in this forum is it can be vary a bit from that.

[Quickslick4444]

Without the battery i was gettin around 9.5 volts from the alternator. Is that low?

[monkeyracing]

Yes. With the car off you should get 11-12 volts at the battery. With the car running you should show 13.5 to 14.7 volts, at the battery.

If you get low voltage with the car off, but good with it running, then you've got a bad battery. If you get good voltage with the car off, and either no change or a drop with the car running, then you've got a bad alternator.

[Tim]

Need a new alternator? I have 5 for the carb'd Festivas.