Hello everyone...
When I turn my wipers on low the turn signal indicators light up and stay on, and the fuel guage goes down past empty. But when I turn the wipers on high the signal lights go out and the fuel guage goes back to normal.
When I turn on the headlights and then turn on the wipers, the wipers act weird and sometimes stop a second or 2 and start to work again, and sometimes move about an inch up then go back down.
When the wipers or headlights are on, the turn signals are very slow.
While the car is running the volt meter only shows 11, any suggestions?

72 chevelle 454, 1 wire alternator.

Everything the low voltage is probably do to inadequate dash harness grounding. Do you have an SS dash or the sweep dash? The two have different grounding.

The low voltage may be related to how the one wire alternator is wired. If the alt output is wired directly to the battery, you can expect lower voltage at the fuse block. The original configuration is to wire the alt output to the horn relay. When wired to the battery you add extra wire and the fusible link to the dash power feed. The increased resistance results in a higher voltage drop. Any alternator should have the output wired to the horn relay.

I have the sweep style dash. The alternator is wired direct to the battery.
The volt guage was reading around 13 with the engine running about a week ago.
Then I noticed the problems I stated in the previous post, and the starter began turning over slow, so I figured it was the battery and bought an Optima battery, and that didn't help.
http://www.autozone.com/images/products/jci/jci75-25002.jpg

There is a ground wire on the parking brake as seen in the attached pic.

Depending on the amount of current flowing to the dash the voltage will vary. The more current headlights on, wipers on, heater on, the lower the voltage will be at the fuse block.

The original harness had a wire connecting the external voltage regulator to the horn relay. It was used to measure the voltage at the relay and regulated the alternator output accordingly. The alternator would have been set to maintain about 14.5 volts at the horn relay.

With a one wire the internal regulator maintains the voltage at the alternator output terminal. The voltage at the horn relay will vary depending on the current flowing through the 10 ga wire connecting the horn relay to the junction block and the 14 ga fusible link from the j block to the battery positive.

From the horn relay to the dash harness there's another fusible link a 16 ga and 5-6 ft of 10 ga wire. Again depending on the current flowing the voltage at the fuse block can be considerably less than the regulated voltage at the alternator output.

With a one wire alternator and the output connected to the battery. As the current demands increase the voltage at the fuse block will drop.

Measure the voltage at the alternator output. If it is low you have a changing problem.

http://www.chevelles.com/showroom/data/500/70grd2.JPG