optima wont hold charge [Archive] - GrandAmGT.com Forum


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08-11-2006, 10:40 AM
ok heres the deal..this is in my buddys 99 grand am 2.4

brought the car out of storage and tried to get it running but it wouldn't so we figured out the the alternator and battery had to have went during storage. we had the optima redtop replaced for free under warrenty and had a new mr alternator high output over nighted and put in yesterday.

everything went good and the car started fine and the volt meter was reading 14.4. afterwards we were sitting around and working on other parts of the car and left it running and i noticed the volts dropping slowly and went all the way down to 10.4. we turned the car off and started it a couple hours later and the meter read 14.4 again but after a couple miles of driving they drop down and stayed around 10.5 and it is doing it again today. we did upgrade the wiring from the alternator to the battery also but i just have no idea why it isn't holding a charge at all

cliff notes: replaced battery and alternator with optima redtop and alternator and now it wont hold a charge at all, but it does fully charge while the car is off for a while

08-11-2006, 10:10 PM
are u using the top mount posts or the side mount. i have noticed tha tmy top mount posts are having trouble staying firmly attached and sumtimes i can pull on the mount and it slides right off.

Mike Jung
08-11-2006, 10:20 PM
Sounds like a bad alternator to me, or related to the charging system somewhere.

Fully charge the Optima RedTop battery with a battery charger.
Let it sit over night.
Check the voltage in the morning.
Should be around 12.65V if nothing is on/or used before checking the battery.

Then drive or run the car for 15 minutes, & then check the voltage at idle.
(When you first start the car: the alternator always runs at a higher level to charge the battery, & because the rpm's are higher.)

08-11-2006, 10:26 PM
What's the rating of the new alternator as compared to the old one? It may be just that the old one could produce enough power at lower rpms whereas the new one can't do the same. Its just a guess but check the power coming from the alternator before you dismiss it as the bad part.

08-11-2006, 10:50 PM
The alternator is not working. Check your wiring for a broken connection or wire. Also double check your upgraded alt to bat wiring to make sure everything is tight and connected properly.

08-11-2006, 11:56 PM
thanks guys, we checked everything that had to do with the amp and we were using the same post that the stock wire was comming from. all the wires we hooked up right so im guessing i just got a bunk alternator. we threw his old one in and with all his lights and stereo system running its sittin around 13 which is good enough for now. we are gonna send back the alternator and hopefully we can get a full refund

thanks again guys