16Sammy61

When i bought the car it had to be jumped to run. The battery was tested and was considered "ok". Not the best but usable. Sometimes the next day it would be dead. Sometimes it would barely start the vehicle. So i finally made it and bought a brand new battery for it.......... Not any better. When you turn the key it sits just above the red spots(you could say it was similar to...a crosshatch?), not sure what it is but im sure someone knows what i mean. And while the car is running, it sits just above the line. Is this common? I feel like it should have more charge than barely enough to start it every time

parkers Z28

Check to make sure you have good connection on both sides of the battery +&-
Check to see if the battery is getting a charge
do you have a multi meter ?

16Sammy61

Yes the battery is new and it had a good charge the first time i started it. The new battery can hold just enough to start the car, which is pretty much where the last was. I do have a multimeter. Just curious as how much charge the battery should hold regularly. Even when the car is running, it barely sits above the halfway mark.

Injuneer

Two things to check:

1 - Is the alternator properly charging the battery. Sounds like it may have a problem with the voltage regulator. When you first start the engine, after a weak start, what voltage does the dash gauge indicate? Typically, if the battery has been drained, the initial charge may reach 16V to replace the lost stored power. Then the system will pull the voltage back down as the battery comes up, and the voltage should sit around 13.5V. Since the gauge is only "numbered" at 8V on the low end and 18V on the high end, you have to interpolate the actual reading. Assume the middle mark is 13V, and base your readings on that. At first start, voltage should be well above the mid line. At normal idle, it will be very close to the mid mark. Sounds like it's OK at idle.

2 - If the alternator is fully charging the battery, is there a parasitic drain on the battery when the engine is off? Do you have a large audio system or some other accessory that could be pulling power even when the ignition is off? Are the interior lights staying on?

16Sammy61

Usually at idle after a weak start it sits just above the middle mark. However, usually the weak starts are caused by the battery barely having enough to start it.

Not sure if alternator is good, but seems like it is. It used to somewhat charge my "ok" battery. One day it started to make noise, but the next time the engine was started it didnt.

There is nothing out of stock audio in the car. Actually as of recently there is no rear speakers, and the radio wire is shorted so it usually isnt on. It is turned off to be safe anyway. Interior lights always are working when the doors are opened, but go off when the door is closed as they should.

After all, i guess the battery is good. Since at idle is does sit around the mid mark. Just figured it would have more charge when i start it.

Injuneer

That's the point. If the battery is drained, for any reason, the alternator will increase the voltage to recharge it.

This is something that has to be tested at an auto parts store.


The fact you may have a shorted wire could be a clue. The radio has two power sources. One is switched on and off when the ignition is switched on and off. The other is a constant supply, never switched off, for the purpose of holding the memory in the radio - presets and security.

You need to measure the amps draw from the battery when the ignition is switched off. This requires putting an amp meter in series with the red/positive wire from the battery to the "+" terminal box. That should show a draw of less than 0.10 amps. If it is larger, something is pulling power that shouldn't be. You start pulling fuses to see which one causes the amp draw to be reduced.