Well as you've probably read, I've been having a terrible problem with my voltage @ idle. When I'm driving it's fine, but when I stop at a stoplight the voltage drops super low and all my lights dim. I now have a sub with 400w amp but the problem was there way before I got that, so that's not to blame. The other day I got fed up so I went and bought a Duralast Gold 105 amp alternator. I installed it but of course it didn't even help. In fact, my voltage now is even lower at idle and I'm idling at 5,000 rpms!!!!!!!!! I took all the wires off and all the grounds and sanded everything clean; I even put a new connector on the end of the wire going to the back of the alternator...Still no change. Although the other end of that wire was grounded to a bolt which also held the positive battery wire. Not sure if that means anything. Today I went to buy a new plug to go into the back of the alternator..because someone mentioned that could help. But the dude at autozone assured me that wouldn't make a difference seeing as my battery is 100% charged. I also just installed a new starter. Another guy at autozone said it's because my dual fans run constantly with the car on. That makes sense, except for I just installed a switch to turn them on and my voltage is still the same. Anyone with ANY possible solutions, please let me know because I'm at the bottom of the barrel and I have no other ideas Thank you .

 

1991 Camaro RS 305 TBI Automatic
- http://www.angelfire.com/freak/chris...ce/camaro.html
-Dual Catback Exhausts w/ flowmaster
-Dual Cooling Fans
-Edelbrock Open Element Air Cleaner w/ K&N
-Alpine CD Player
-Power Acoustiks 400w amp
-JBL 12" Subwoofer
-Saving up for a 350

 

My old LG4 used to do this. I never really got it under control as I would have liked.... My iroc does this too. Even with a new batt, alt, and a capacitor to keep the bass thumping..... I am at a loss man. How are your RPM's at idle??? Low? Maybe bumping them up a hair might make this more managable. My fan is always on too, and was on my old car, didn't affect it.
Hope it all works out man!

Will

 

3rd gen gauges are notoriously inaccurate. My volt gauge reads a steady 10 volts whether at idle or in motion. However, when I check the battery terminals with my voltmeter, I get a good 13.9 volts (at 600rpm idle.) The gauge is just THAT far off.

I'd recommend checking the voltage with a reliable meter before you go replacing the entire wiring harness. You may just have a worn-out gauge.

 

Thanks..Yeah the gauge might be off but its definite that I have a serious voltage problem. When I stop at a stoplight now and turn on my blinker my voltage gauge jumps up and down with the motion of the turn signal while going very slow. It also does this with bass. But after taking off the lights all get brighter and my voltage guage is back up to around 14. (After installing the switch for my fans, with the switch/fans turned off, the voltage is a tad better). Any ideas?

 

Thats pretty normal. The Gauge is supposed to pick up on current draws, and when something like the blinkers are sucking power, the gauge will pick up on that. I have seen some gauges that react slowly and others that just bounce around rapidly to current draw. Best of luck man

Will

 

I have 2 suggestions for you to try.

Is the belt to the alternator pulled tight??? Not sure what car you have if V-belt or serpentine belt. Just a suggestion.

Second suggestion is just a simple one. Are you running the correct gauge cables to the batter? The fatter they are the better if they are to thin then you are losing amps.

It is like trying to jump start a car with those cheapo jumper cables that drain much of the AMPS before it gets to your car. And that is because they are too thin.

Try those out and see if you find anything. I am kinda betting that you have a wirring problem somewhere.

 

You're not running underdrive pulleys are you? Also try to get a 140 amp alt. You can even retrofit a 4th gen alt to a 3rd gen. And if you're using a remanufactured alternator trash it they are junk. Being that it is a '91 it has a serpentine drive system so you probably don't have any drive issues unless you are using underdrive pullies those things are a waste. They cause dead batteries and do very little for power. I don't use my March alternator pully anymore because of this. I do use the water pump and crank pully. They do look pretty and I've got them so why not.

 

Is your engine grounded?

That may sound funny but as your car gets older, the "ground" points in the entire electrical system begin to weaken from corrosion, etc.

Here is an EASY solution. Just go buy a 2 or 3 foot battery ground cable and attach it to the engine on one end (via a bracket bolt or some such thing--I grounded mine to an AC bolt on its bracket) and the fender or frame at the other end. You WILL be grounded after that!

Also, you may need a 140 amp alternator to drive a 400 watt amplifier. Some folks run two or three alternators in order to keep up.

I know you may not want to hear this but it is coming from a professionaly trained audio engineer. You DON'T need 400 watts and two giant subwoofers in the back of your Camaro in order to reproduce ACCURATE bass. When bass frequencies are amplified by that much power (relative to the rest of the audible spectrum) you are DISTORTING your music GROSSLY

50 watts of acurately amplified music is GOBS for a car

 

Wait...Where do I ground the 2 points? Sorry, could you go into more depth on the locations? Btw, thanks so much for the idea.

 

OK, understand that what we are doing is grounding the car's electrical system. When you attach one end to a clean steel point on the engine, like I suggested you use one of the brackets on the AC or any other handy bolt attached to the engine, and then attach the other end to either the frame or fender, you are creating a perfect ground for the electrical system. Nothing should be able to escape it.

It is just a plain old simple ground that serves EXACTLY the same purpose as the ground cable on your battery.

Hope that helps

 

Ok, well I attempted it and there was no change. But let me know if I did it right. I went to autozone and I bought a 30 inch 4 gauge side terminal battery cable. I unbolted the screw attaching the black bar going from the AC to the engine. Of course I sanded them both clean. I bolted the bigger end of the cable on there and bolted the other end to the passanger strut screw. Did I do it correctly? Thanks

 

Yup.

You are now as grounded as is humanly possible

 

im having the same problem my guage is do delicate it even drops when my brake ligths come on o have a 200 degree fan switch which is always running because my car will never get that cool when i hit the brakes with my fan on and blinker on and my head lights it gets very low im in the market for a 140 amp alt because i desperatley wanna run underdrive pulleys

 

Hey sitting bull, even though that didn't work I want to thank you very much for the idea. Do you think replacing the + and - battery cables might help my voltage problem?