low voltage and sputtering issue related?

**JayTA98** · 01-20-2013, 06:30 AM

Hi guys. I have a question. When i use a battery load the CCA drops to 200. The battery is rated to 720 CCA. Does this mean the battery is bad? The scale reads its weak. The battery is a red top optima and is about 4 yrs old. I don't think i have issues with it but my voltage is going down to 11.6v when the fans, headlights, a/c are on. When the fans are off it does better. When the car is idle is when i see the low voltage. While driving it stays around 13.6-14v. Its almost like the alternator is not charging enough at idle. I had this issue for a while and i never the car stalled.

Yesterday i started the car and it was hard to start and it looked like it there was not enough fuel pressure. it lasted for about 7-10 secs. I give it gas and eventually goes away. I turned it off and tried again. Same thing happened. It drove fine all the way home and i tried to replicate the issue but it was gone. I checked the fuel pressure and is priming all the way to 58 and i have 60 while running. I don't think this issue is related with the charging issue.

Any ideas on what to check?

**eteller** · 01-21-2013, 08:08 AM

Any codes? Under load it probably will not charge at idle, I might be wrong with a LS1 but on a lot of cars you have to hit 2-3k rpm before any charging starts.

**JayTA98** · 01-21-2013, 11:28 AM

Originally Posted by eteller

Any codes? Under load it probably will not charge at idle, I might be wrong with a LS1 but on a lot of cars you have to hit 2-3k rpm before any charging starts.

No codes. All cars i owned never drop voltage like this unless there is an issue. I guess i can upgrade to a bigger alternator

**eteller** · 01-21-2013, 11:49 AM

Originally Posted by JayTA98

No codes. All cars i owned never drop voltage like this unless there is an issue. I guess i can upgrade to a bigger alternator

No reason to upgrade the alternator unless you got a monster stereo or Mad Max apocalypse level lighting. What are you checking the voltage with the stock gauge or a decent multi-meter?

**JayTA98** · 01-21-2013, 12:25 PM

Originally Posted by eteller

No reason to upgrade the alternator unless you got a monster stereo or Mad Max apocalypse level lighting. What are you checking the voltage with the stock gauge or a decent multi-meter?

Decent multimeter.