Battery voltage is it enough
Thread Starter
Intermediate
Joined: Sep 2006
Posts: 41
Likes: 0
From: Jacksonville Fl
Battery voltage is it enough
My battery charges up to 12.6 volts on my charger. I have a 96 Lt-1. Stock. When I turn the key to start I'm getting 11.4 volts on my digital display, so my question is : Can this be keeping my car from firing ? Does the system have to have more than11.4 volts ? It seems everything else is ok with the exception of maybe the ignition module ground of the blk/wht wire, it shows grounded with key on and with key off....
Instructor
Joined: Apr 2007
Posts: 127
Likes: 0
Your battery voltage at the end of charge should be about 14 V. It will be less after it sits for a while, 12.5 to 13 V. If it is reading 11.4 V you have a bad cell. That could cause starting problems. When the engine is running it should read over 12.5 V. Most 12 V systems I have seen run 14 to 14.6 V engine running.
I'm not sure if I understand if your engine will start at all but a weak battery can crank, but the starter is enough load to to cause little or no spark.
I'm not sure if I understand if your engine will start at all but a weak battery can crank, but the starter is enough load to to cause little or no spark.
Thread Starter
Intermediate
Joined: Sep 2006
Posts: 41
Likes: 0
From: Jacksonville Fl
My battery
Whenthe car is cranked over with the ignition switch I see 11.4 volts on my digital display of the instrument panel, the car will not fire at the coil so I was wondering if this voltage only being 11.4 could be the cause of the system not firing the coil? Also I talked with Chris and found out that maybe I have a problem with my air pump circuit because when my car ran my air pump would turn on with the key in the on position and now when I turn the switch to the on position I do not have an air pump running. Could the relay be burnt causing to much current draw and pulling my starting voltage away and not allowing the system to fire??
Team Owner
Joined: Mar 2001
Posts: 54,124
Likes: 30
From: Cincinnati, Oh USA
The dash voltmeter reads low when the engine is not running and cannot be trusted. Use a test voltmeter. If your engine cranks at normal speed, your battery is ok. After charging and sitting for 24 hours, 12.9 volts or higher is fully charged, 12.0 volts and lower is discharged and linear in between.
During cranking the battery terminal voltage should not fall below 9.0 volts or the battery is discharged, the battery connections are not clean and tight or the battery is at the end of its life.
During cranking the battery terminal voltage should not fall below 9.0 volts or the battery is discharged, the battery connections are not clean and tight or the battery is at the end of its life.
