Is 11.5 volts enough for a proper start?

[G Winter]

GM OEM gauges are good for relative measurments only . I never had trusted them.

 

[vetteboy86]

I would say that much of a difference is way out of range. What is the meter reading when the car is running and the alternator is charging? because at that difference you have the potential to do some damage. Also how did you check the voltage and with what kind of meter?

 

[Tuna]

Just thought I'd jump in here. My 92 generally shows in the mid to high 11's before starting and it starts just fine. When I start having start issues, I usually see low 11's or 10's on the volt meter and the 'SYS' message starts flashing on the center part of the dash.

After starting, the volt meter shows high 14's for a while - this indicates that the charging system is putting out a good amount of volts. But, it does not indicate the condition of the battery.

I watch the volt meter after driving for 20-30 minutes and I expect to see the charge voltage drop to the 13.8-14.0 range. This appears to be normal for my car with a good battery.

My Radio Shack digital volt meter and the cars volt meter seem to follow each other pretty good - so, I'm in good shape there.

 

[Rabbit]

I would say that much of a difference is way out of range. What is the meter reading when the car is running and the alternator is charging? because at that difference you have the potential to do some damage. Also how did you check the voltage and with what kind of meter?

Checked the battery with a VOM. After start charges at 14.7 volts. Got curious so I checked my CTS & got the same results. This is with the battery connected & sitting for 3 0r 4 days. I usually disconnect the battery when the weather is bad & don't drive for a week or so. Then the digital will register 11.7 to 11.9 prior to starting.
Guess there is a little loss thru the lines & the usual draw.

 

[Rabbit]

Checked the battery with a VOM. After start charges at 14.7 volts. Got curious so I checked my CTS & got the same results. This is with the battery connected & sitting for 3 0r 4 days. I usually disconnect the battery when the weather is bad & don't drive for a week or so. Then the digital will register 11.7 to 11.9 prior to starting.
Guess there is a little loss thru the lines & the usual draw. There is no cranking issue & it fires right up.

Ciao,