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Car won’t start, wondering if it’s my battery

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Old Nov 23, 2023 | 12:45 AM
  #1  
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From: MD
Car won’t start, wondering if it’s my battery

Hello, I have a 1986 gxl and I have no idea what’s wrong with it.
ive been having battery issues for a while now but my car won’t even start any more
ive had this car for 3 months and I’ve gone through 3 different batteries
i replaced my alternator
autozone tested it and said it was good

but I’m having a problem starting the car now.
for some reason my car drain batteries like there’s no tomorrow, so I’m constantly charging them from like 50% to 95%.

I bought a red top optima battery (first time trying this kind) anbout 2 weeks ago and my car wouldn’t start with it, I put it on the charger and turns out it was at 50%!

so I charged it and it worked! Car started up!

I’ve been having other troubles blah blah blah so the batteries keep sitting, and I have to charge them again.
at this point I’ve charged my red top optima battery from usually around 40% to 100% about 5 or 6 times now.

today I tried to start the car and it cranks and cranks and cranks but it just won’t start.
i think in flooding the engine so I looked up how to fix that and I was told to unplug a certain fuse and crank the engine for 20 seconds blah blah blah and then plug the fuse back in and try it again, so I did that about 4 times (it didn’t start) and I gave up and went inside to check the batteries charge. It was at 32%.
I was out there for like half an hour.
what is my problem???? Should I buy a new battery? I just got this thing!
im worried I’ve killed it.
any suggestions on how to get my car running again and what my problem is would be greatly appreciated!
long story short my car won’t start at all with any of my batteries.

Also should the batteries be draining this fast or am I doing something wrong?

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Old Nov 23, 2023 | 12:54 AM
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e hankey's Avatar
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From: MD
Also when trying to start the car the battery gauge jumps from around 8-9 volts, I just thought of that.

that’s probably my problem, what do I do about that? What’s causing it?
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Old Nov 23, 2023 | 08:40 AM
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Sorry to read about your troubles. It is hard to say what exactly happening here. You can have the battery tested a a parts store. A half hour seems to be a long time to be cranking and not kill the battery. You can check for parasitic drain, some is to be expected. It shouldn't be excessive, though. If you haven't already check the cabling and connections in the charging and starting system. Clean the connections and coat lightly with dielectric grease. I have an 87 GXL, these cars are almost 40 years old now and electrical connections are very important. There could be more to this so, keep your eyes and ears open.
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Old Nov 23, 2023 | 12:43 PM
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not sure if i'm missing something, but it sounds like something is staying on in the car, and that it's a pretty high current device. you need to find it and either remove or fix it.

you might have obvious candidates for the drain. anything that's in the car, that was added (radio, fog lights, alarm, etc.) - check those first.

if one of the car's factory circuits has gone awry, then it will be less obvious and you will need to start pulling fuses while testing across the battery.

https://shoptoolreviews.com/automoti...y-drain/34587/

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Old Nov 23, 2023 | 01:01 PM
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From: FL
here's a video that might help you out


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Old Nov 23, 2023 | 04:09 PM
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You didn't mention how long (hours? days?) before your battery drains, but to save you any inconvenience disconnect your negative battery cable when the car is to sit for a long time. I know it's not a fix for your problem, but it will save you the inconvenience of needing to frequently recharge your battery.

Obviously, you've got a short somewhere that's draining your battery. To find that short, connect a DMM with (10A) ammeter in series with the positive (+) terminal of the battery and measure the current draw with the key off. Next, pull each fuse and note when the draw disappears. That's the circuit where your problem lies. Next, check everything out on that specific circuit until you find the short. It's a tedious job, but basically it's just a process of elimination.

Just because you've got a new alternator doesn't mean that it's not the cause of the current drain. It's also common for the regulator or a diode in the alternator to fail, resulting in a draw. As above, with ammeter in series with battery, disconnect the alternator lead and check the current draw.

Good luck!
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Old Nov 23, 2023 | 05:34 PM
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You'll need to use an AMP clamp on each circuit coming off the engine fuse block to narrow it down. Don't start the car during this test. Your battery also needs to be fully charged. Once you know that circuit, you need to see what runs from that circuit and remove each fuse from the inside fuse block to narrow down even more.
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Old Nov 27, 2023 | 10:44 AM
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From: Rancho Cucamonga
Just a quick note of commendation, I almost gave up on these threads for all the know-it-all flaming that goes on. But after reading this one let commend all the guys that lent thier advice and help to this fellow rotary enthusiast, it was very refreshing to read.
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Old Nov 27, 2023 | 12:03 PM
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Does your car have an alarm?

The dying car alarm in my old Mazdaspeed Protege used to kill the battery, and also randomly kill the ignition even when the battery was good.

We ripped that old pile out and the car ran great. Hopefully it's something as simple as that for you, because it took us awhile to find the culprit, too..
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Old Dec 19, 2023 | 04:20 PM
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From: Usa
Originally Posted by diabolical1
here's a video that might help you out

https://www.youtube.com/watch?v=zdIKNnwEjIs
this was great, thanks!
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