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madness410
08-14-2012, 05:33 PM
hey everyone. got an issue i need help diagnosing but i think i may know what the problem is. the last 2 days after starting my car the voltage would be at around 12...then after idling for 30-40 seconds it would go up to 14 or so. today on my way to work i noticed the needle for voltage on my car was bouncing back and forth, steadily between 13-14..abnormal because the needle is usually still. after that it began to drop drastically, and eventually was barely bouncing between the red on the gauge and off the red, the check gauges light was going on and off too. also when i hit the gas on the highway the voltage would somewhat go up and once i took my foot off the gas it would go back down.

i read up on symptoms of an alternator going bad and this was one of them..looking to see if anyone has any similar experience with this. i also recently installed a new belt tensioner, but i dont think it has anything to do with it. motor is a 3.8. thanks for the help in advance

Jon

WildBillyT
08-14-2012, 06:21 PM
Alternator is on its way out. Get it tested.

NJ Torque
08-14-2012, 08:43 PM
Alternator is on its way out. Get it tested.



Yup do a ripple test before you lose it on the side of the road.

MyFirstZ
08-14-2012, 08:50 PM
Yeah the diodes sound bad in the alternator. It's super easy to do the alternator in the 3.8.

madness410
08-14-2012, 10:52 PM
yeah ill get it tested at advanced or something before i get a new one.

its easy to remove i did it the other week when i replaced the tensioner. whats the worst that can happen if i drive it on 12 volts

creeper
08-15-2012, 12:36 AM
double check the connections are good and tight since you just removed it

I wouldn't drive it at all unless you have AAA and nowhere to be. Just two days ago I had one die on me in an Explorer. It went quick, luckily the radio shut off and gave me enough warning to get off of the main road before it died and I lost power steering, power brakes, etc.

madness410
08-15-2012, 03:21 AM
haha i was gonna check the connections until i heard it start up..sounds like a huge rod knock in the alternator itself...im pretty sure its toast. replacing it hopefully tomorrow. thanks for the help guys.

greenformula92
08-15-2012, 10:37 AM
Yeah that alternator is toast. They put of quite a show when they actually go...I would know I have had one blow in my face while diagnosing another problem lol