86 Coupe GT. Intermittent low voltage

[kutnicks]

Hello Everyone. I'm hoping someone will be able to provide some advise.

Problem:
1. Voltage gauge reads low voltage (about 8V).
2. Low voltage confirmed (all lights are very dim)
3. If the headlights are turned on and the heater fan is on, the car will stall
- Seems to be due to lack of enough power
4. When the vehicle is just sitting in Neutral the voltage will go up to about 10V

Randomly the voltage will head back up to about 13V for a few minutes. While at 13V I can operate both the heater fan and headlights with no problem or drop in voltage. After a couple minutes the problem will start again.

Does this seem like an alternator or voltage regulator issue? I didn't think that it was possible for the alternator to work some - I thought it was all or nothing.

Does anyone have any thoughts? Thanks in advance for your advise.

[marksaudi]

yeah altenators can have intermittant faults like that i think it prob your altenator is on the way out if you check the altenator output with multi meter on the positive post on the back of altenator with engine running you should get approx 14 volts if all ok. much less than that and i would replace altenator