This is a wierd one.

I was driving to a customers house tonight and I met up with him at a Sams club parking lot. I went to unlock the doors with the key and the alarm went off. I quickly put the key in the ignition and nothing happened. Then noticed that everytime I turned the key the clock would reset and none of the interior lights came on. The guy jumped started and it fired up, went to his house completed my work then tried to fire it up and nothing. At this point I had to assume that my week old battery is faults, especially since I just had the alternator tested when I put in the new battery. The guy jumped me again and I was off only to stall out about a mile away. My wife came out with a battery that we had laying around along with my jumper cables. I put in the other battery and realized that it would not kick over the Disco so I swapped back in the other battery and before I could jump it I then fired it up and it started no problem. I then figured since my wife was tailing me that she could follow me home for the 20 min drive just in case. Low and behold it made it back to the house just fine and I even restarted it after I shut it down after pulling into the driveway. I was thinking that the alternator was only pumping out 12.9v a week ago at idle that it must have just been a coincidence that it is going out, I have no idea since it seems to be charging good enough at higher RPMs.

I have heard also that when your alternator is going out that your tach will flutter or fluctuate a little. I really do not want to drop 200.00 on a alternator if I dont have to but I do not want to be in that predicament again.

 

Go down to one of your local auto parts stores and have them check the battery and the alternator for charge and draw. Make sure to clean and check all cables and ground first just to make sure you have everything covered.
The alternator and battery should be up around 14 to 14.6 volts to be healthy, get down in the 12 volt range and you have problems brewing.
Mike

 

Just got back from autozone and the battery and alternator are in great shape. today I am cleaning the hell out of my electrical terminals.

 

Idle charge was at 14.01v and 1500rpms it was 14.4v. It has to be a connection or a ground.