did my alternator just go to hell?

[johnwc723]

alright i was drving along and i noticed that my tachometer started floping all over the place also my lights would be bright and then all of a sudden they would dim, it wasnt effected by my engine RPMs (not what the tach said because its messed but by sound)

i checked my battery voltage while its running yesterday it was about 11V and today its about 12V when I checked

Im also hearing this different noise from my engine than usual and it seems that i have less power than i used to (my engine almost stalled today when i pulled out the clutch as normal)

does this sound like an alt issue ( im almost positivie it is) anyone had this problem and can give their 2 cents on whether they think it all need to be replaced or just a part etc (if its the alt)
also where is the alt, i think i might be confusing it with the starter hmmm...
THANKS SOO MUCH GUYS
it all just has to happen to me :(

[k-roy]

It sounds like the alternator since the battery still has a charge. I had similar issues when mine went bad.

[johnwc723]

damn! anyone else have some insight, since it prolly is an alt is it bad for it to drive it now that its messed (until i get new one) also does it look like a certain part has gone wrong thati could replace (lol i know this is a bit much considering no one is looking at my car right now!)

[k-roy]

Check all the electric connections on the alterntor, startor and battery. Clean the battery posts. Its not too safe to drive it around if it is the alternator going bad, It could kill your battery as well. Also make sure the belt is not slipping.

[zero.counter]

If you have the time, you could either remove the alternator and take it to an autozone/advance auto parts/pep boys/oreillys/etc. to have it tested for free, or you could perform a self diagnosis to determine its' operation.

To perform the latter, start with a voltage test. Turn the engine off and I usually discharge any surface charge by letting the headlights run for about 20 seconds, then turn off. I use a Digital Voltage Ohm Meter by setting it to DC and probe across the battery terminals. Measure the figure provided by the DVOM and write it down somewhere, on you arm or whatever.

Then come the second step, or NO-Load test. You can connect a tachometer to the engine which you can buy from any auto parts store for a nominal fee unless you have an extra laying around. Make sure that no electrical loads are present, including closing the doors for the jamb sensors. Turn the engine on and up to 1500 RPM. With your probes still attached to the battery, measure the load at the 1500 RPMs (steady). Your voltage should have raised about a half a volt but for ure not more than 2 1/2 volts. If voltage doesen't move up more than half a volt from your original reading (voltage test), then the alternator is not charging. If it goes past 21/2 volts, then the alt is overcharging whcih is a big bad NONO! :)
If the voltage is good and within those figures, then you can move on to my next and freakin last test....the LOAD TEST. If the alt failed, then take it to the stores I talked about earlier to have it thoroughly tested.

Now, for the last part, the LOAD TEST as we call it, since it does what it says. With the engine still running, turn as much stuff on as you can in the car. High beams, blower, stereo (with the 10S), and anything else you can throw at it. Increase engine speed to 2k RPM and hold it around there. Now measure the voltage from the battery now. It should increase by at least a half a volt from the control measurement, if not, then again...take it to be tested for integrity.

I have experienced this before and felt that it may benefit you somewhat. :)

[MrBen]

Here is mine when my battery died. Yes I know the image quality sucks, so don't complain, I'm not rescanning them:

http://www.geocities.com/benzdroid16/1.txt

http://www.geocities.com/benzdroid16/2.txt

http://www.geocities.com/benzdroid16/3.txt

http://www.geocities.com/benzdroid16/4.txt

[1988starter]

my car did that with a loose battery ground wire

[johnwc723]

damn i hope mine isnt spiking upwards of 50 volts like yours is!! well im not drivin it till i get a new one anyways... thanks for all the help guys!