i finally got my volt guage installed on my 91. i was wondering what it should be reading when the engine is running. when my engine is running now it goes up to 13 volts. i turn the engine off so that the lights on the dash are still one and the volts start to drop dramatically. does this sound right or am i going to have to replace something soon. enlighten me thanks

Well, I use my greddy turbo timer as my voltage meter. I hacks into the ignition so that's where it measure voltage from. When the car is first turned on and cold, it reads about 13.3V. After the car warms up, it reads 12.7V. When the car is off, it reads about 12.0V. This is with a Miata battery relocated to the trunk. It reads higher when the car is running because of the altenator.

Khiem

Sounds right except for the "up to 13 volts" when running.
Your gauge could just have an offset to it.

FWIW, this is why car mfg's don't put many gauges or accurate gauges in cars. Uninformed owners would be taking their cars in all the time with questions of "my gauge is all over the place - it can't be normal!"





Originally posted by knightrider
i finally got my volt guage installed on my 91. i was wondering what it should be reading when the engine is running. when my engine is running now it goes up to 13 volts. i turn the engine off so that the lights on the dash are still one and the volts start to drop dramatically. does this sound right or am i going to have to replace something soon. enlighten me thanks