2_point8_boy

check it out, my voltage guage keeps reading that the alt is putting out 14 volts, then 12, then like 8, it just keeps jumping around at random times. when i first start the car, it always makes 14 volts and holds there, then when the car warms up, it changes to something else and hold for a little while, but it's never a steady 14 all the time. I was thinking that it had something to do with the wiring harness that goes into the alternator. if the connections are loose inside the connector it would mess up the output voltage because one of the wires cariies the exiter current, right? I was thinking about putting some kinda grease or something that conducts in there to make up the gap, do you think this would work? what other things would cause this??? Just so you know, I've already put 2 new alternators on it and the problem remains.

Danno

Thats pretty normal. After a cold start the alt throttles up to recharge the battery and will stay there until either 2 things happen. First the battery terminal voltage comes up enough for the regulator to back down charging rate or the regulator senses high temp internally and it will also back it down. Normal with the exception of the 8 volt thing, only time I see them jump down like that is with the A/C running and cooling fans cycling at idle. Usually its only a momentary dip reflecting the large current draw then it will inch towards 13 volts or so as the alt changes its charge rate. With a 105 amp alt with all the crap running it tends to stay around the center of the guage. If it changing radically with no change in load on the electrical system then perhaps it IS time to start checking over the electrical system. Worn brushes in the alt will cause erratic charging right before they bite the bullet but a new alt should rule that out. All the normal stuff as far as troubleshooting applies.

2_point8_boy

Yeah, the alternator that i have on there right now is only like 2 weeks old, so the brushes better be damn dine. I think that it has somthing to do with the harness that attatches to the alternator. It doesn't clip anymore.

I was wondering if there is somewhere that I can get just a new clip for that end so that i don't have to replace the entire harness since that is the only end that has something wrong with it.

I noticed that when I mess with that connector that it goes right back up to 14 volts, that's what leads me to believe that it has to do with that. Anyway, here's a better description of the symptoms.

I start the car and the voltage is right at 14 volts, it holds steady there for about a minute, then starts to jump around. The needle looks like I ran over a bump and it is just jumping up and down. At times it decides that it wants to hang around 8-12 volts, way below what i would even consider normal. It just decides to change at very random points, so there isn't really any kind of definite pattern to it.

Is Di-Electric grease a conductor or insulator. i was thinking that if the contacts in the harness are just worn and don't touch all the time, that shoving some of that stuff up in there would help to make up the small gap that might be causing the problem. I didn't know how that would affect things, so I decided that I would ask before I did anything.

Thanks,
Jeff

Danno

Its an insulator. You can buy the plug shell or housing at most auto stores and with the proper pin extraction tool replace it. Some places like pep boys have replacement connectors with a short pigtail that you can easily splice into the existing harness. Online try www.alternatorparts.com. They stock all sorts of parts for all types of alternators and support components.

83_1/2 L69

The volts guage might be lying. Do you have a handheld volt meter. Measure the voltage at the battery. The most acurate place to check the voltage inside the car is at the cig. lighter. I had a similar problem, it was a bad connection in the circut that feeds the instr. panal.

2_point8_boy

cool, thanks guys. i do have a handheld meter, but I have to buy another since I left my current on in th ecar and the LCD got cooked from the heat. Thanks for the info though.

91rsCAMAROwTN

:hail: Hello my 91 RS does the same thing .....right after i got a new alt. i started noticing the same very problem do i need to worry about it.....I thought it was my battery connectors with corrosion but i changed them both completely and no didfferents? What gives?

Thanks for any help?

2_point8_boy

I havn't noticed that my actual battery has been stressed or anything becuase of it. It's mostly just an annoyance.

I'm actually wondering if it's because I have my power wire for my amp connected to a ring terminal that is shoved in between my battery and the cable, the cable kinda bolts it on. I am going to connect it directly to the power feed off the alternator this week and see if that solves the problem.