Low volts

**jamessr** · 06-15-2008, 12:58 PM

guys I need some help.
Here in New Jersey it just starting getting really hot again so I ran the AC for about 30mins. My voltage went into the 10-11 VDC area. I shut the AC off and rolled down a windon and it went back up to 12VDC. I cam here and researched the issue and the search showed that RPM's might be an issue. NP, I got my hand held and changed the RPM value to
Idle AC on +100
Idle AC off no change
My rpm's at idle are normally around 650-700. I dont have any under drive pulleys. I put a volt meter on the battery while unning and I got 14VDC. I guess this weekend I'm going to change the battery because its 2 yrs old. The climate in NJ being hot/cold/hot then cold again could affect it.
So now... I'm guessing my meter on my dash could be wrong, or I do infact have a rpm issue.

I just wanted to bounce this off anyone for possible suggestions.
Its a M6
Exhuast, header,lid, Diable tune
Thanks in advance

**2001NBMZ28** · 06-15-2008, 06:30 PM

If you suspect the battery bring it somewhere for a free load test, or where you purchased it - most have a 3 year free replacement warranty.

**GEARHEADNATE** · 06-15-2008, 07:44 PM

Your alternator could be getting weak. I can read good and charge the batery fine but when you load it down with the a/c, blower motor and the engine fan at the same time it just can't keep up. I get maybe one a month like this.

**thearborbarber** · 06-15-2008, 08:03 PM

Many parts stores will test both alternators and batteries. That way you don't have buy something you don't have too.

**scotthd** · 06-15-2008, 08:07 PM

battery is to start the car the alt runs it I would lean towards the alt....

**qwk93ta** · 06-16-2008, 12:25 PM

I would check the alternator like others have stated........

**darkangel2002** · 06-17-2008, 07:29 PM

I kind of have the same problem, except I just bought a new battery and my battery gauge bounces all over the place it goes up to alittle over 13 Volts and then drops down to about 9 Volts and then back up and down. It does this the whole time I have the car on, anyone know what is going on.

**0rion** · 06-17-2008, 10:02 PM

Originally Posted by darkangel2002

I kind of have the same problem, except I just bought a new battery and my battery gauge bounces all over the place it goes up to alittle over 13 Volts and then drops down to about 9 Volts and then back up and down. It does this the whole time I have the car on, anyone know what is going on.

sounds like an alternator issue. Put a volt meter on dc volts across the battery while the car is running and see if it's bouncing around. If it is first make sure you don't have a loose/corroded wire and if everything looks fine there I'd start looking pretty hard at that alternator.

**darkangel2002** · 06-17-2008, 10:21 PM

Originally Posted by 0rion

sounds like an alternator issue. Put a volt meter on dc volts across the battery while the car is running and see if it's bouncing around. If it is first make sure you don't have a loose/corroded wire and if everything looks fine there I'd start looking pretty hard at that alternator.

Yea I did that and my volt meter is reading 12.25 volts and doesn't move I guess I will be looking at that alternator