Battery or alt.. Charging problems.

[phillabaum03]

Well i bought a 90 tsi yesterday and it was running fine.. Until night came around and i turned on my headlights.. The car started to stall out and would crank like the battery was dieing and then it stalled and died. So i had a friend jump me and got the car home. I put some jumper cables on it and let it charge for 5-8 min and then i drove the car for about a half hour and it died again. Did the same thing and it lasted another half hour. So i charged the battery today and drove the car around today with the headlights off and it lasted forever, something like 4 hours and then it died, charged the battery for about 5 min and it lasted until it became night and then it started dieing all the time when the lights where on.

Ive had alternators go before but usally the dash lights come one really dim. But this time nothing lights up i just see the headlights diming and the car will start to stall out when its gettin dead.

Anyone have any suggestion. That seems like along time to drive if the alternator was bad or maybe its just starting to go bad?

 

[Irrational]

Get the alternator testes for free at your local auto store.

 

[eclipsegsxccca]

if you have a volt meter, you can test your alt. really easy; first start the car put your leads on the battery, it should read around 14 volts, if not, check the 100A fuse in the fuse box under the hood. if thats good, there is a good chance its no good. or just do what the last guy said. but then you wont find out til' tomorrow

 

[phillabaum03]

yeah but ive had alternators tested that didnt pass but they ended up working fine.. That whole idea of starting the car and takin off the possitive terminal doesnt work on our cars does it. I believe i tried it before with a good alt and it didnt work.

 

[luv2rallye]

Sounds like a bad alternator but sometimes a battery with a shorted cell can pull the voltage down so far that it looks like a bad alternator. With the battery charged (eg. by battery charger or jumper cables on for a while) measure the battery voltage with everything off and then with just the headlights on. Voltage should not go below 12 volts (and difference of not more than 0.5 volts) or bad battery (or have large short/drain) . If that ok see here for a quick test of the 1g alternator: http://www.dsmtuners.com/forums/showthread.php?t=226323. If suspect battery drain or short see here: http://www.dsmtuners.com/forums/showthread.php?p=1496998#post1496998