I just installed a pretty good sound system in my 91 RS(305) and whenever I slow down when Im going fast the car dies out on me.Could it be the sound system draining my battery? Its happened a couple times since the install. Any advice?

 

It is definitely a possibility, especially if it has only been happening since the install. However, what kind off system is it (eg. how many amps etc) because your stock alternator should be able to produce enough to keep the battery charged to permit running the sound system. I have installed several systems on F-bodies over the years and never had a problem and this includes a systems with multiple amps. So your system is either pretty hefty or do yo have other electical add on's as well?? The combination could do it. What does your charging gauge show???

A short in the system wiring could potentially do that too i think. might want to double check the wiring.

 

My battery gauge fluxuates with every power accessory that I use is this normal?

 

hmmmmm.....sounds a little fishy. It doesn't really do that on mine. Does it do it with lights and things like that on (with the radio turned off) or only when you put the stereo on too?

One quick test I would try is get a multimeter and place the leads across the battery terminals while the car is running. You should have a good 13.5 - 14.5 volts across those terminals if the battery is getting charged properly from the alternator. A couple variations of the test to try:
1. Take readings with the + lead on the cable clamp and then the battery terminal (verifies if your terminals are corroded). If the reading drops when you put it on the terminal, clean up the terminals.

2. try doing the test without and then with various accesories on and note any changes. If there is a noticable change that your alternator or voltage regulator may be on its way out.

eddie