Car dies overnight
Thread Starter
Drifting
Joined: Mar 2017
Posts: 1,897
Likes: 164
From: Nashville TN
2017 C4 of Year Finalist
Car dies overnight
so I'm having an odd electrical issue. I can drive my vette around town with all kinds of stops and starts, no issue. I can leave it sit for an hour or three, and it will crank just fine. But if I leave it longer, say overnight, it will crank once or twice and die. I can jump it off, and be fine the rest of the day-but next morning she's dead again.
Im torn between bad battery and power drain. I can't think of anything that would be eating power-any common culprits of something like this? It's mostly just annoying. I don't want to spend the cash on a new battery if it's not necessary. I had the battery tested on the car at autozone and they said it's good-but I know that test can have false positives too.
Im torn between bad battery and power drain. I can't think of anything that would be eating power-any common culprits of something like this? It's mostly just annoying. I don't want to spend the cash on a new battery if it's not necessary. I had the battery tested on the car at autozone and they said it's good-but I know that test can have false positives too.
Team Owner
Joined: Jul 2004
Posts: 28,424
Likes: 3,276
From: Hartford WI
I'm assuming you don't have something like a VAT40 to test the draw in the morning so before you go sending it off, have you had the starter inspected? I don't mean the Autozone inspection. I mean having a rebuild shop take it apart and check it out?
I had that issue myself. When you jump it, life is good. Had the battery tested at Batteries Plus and they said it was good. Took the starter to Autozone and it too was good. Took it to a rebuild shop that would take it apart in front of me and it had bad spots and oil from a previous leak that seeped in and caked up.
If that doesn't work, I'd check the battery draw when cranking.
I had that issue myself. When you jump it, life is good. Had the battery tested at Batteries Plus and they said it was good. Took the starter to Autozone and it too was good. Took it to a rebuild shop that would take it apart in front of me and it had bad spots and oil from a previous leak that seeped in and caked up.
If that doesn't work, I'd check the battery draw when cranking.
Le Mans Master
Joined: Dec 2005
Posts: 8,561
Likes: 945
From: Communist Colorado
I would have the battery load tested and also figure out if your alternator is supplying proper voltage by having it tested also. Of course, check connections for tightness... look for corrosion at the terminals.... all the basics first. My 98 Chevy 2500 was doing the same thing. It turned out to be the battery.
Team Owner
Joined: Jul 2004
Posts: 28,424
Likes: 3,276
From: Hartford WI
I would have the battery load tested and also figure out if your alternator is supplying proper voltage by having it tested also. Of course, check connections for tightness... look for corrosion at the terminals.... all the basics first. My 98 Chevy 2500 was doing the same thing. It turned out to be the battery.
Racer
Joined: Jul 2014
Posts: 266
Likes: 20
From: Philadelphia Pa
How cool temperature wise does it get where you are at night? The issue I had, which had the same symptoms, was that when it would cool down my door switch would fail and trigger the dome light. It wasn't consistent though, sometimes they would stick on for a second and sometimes they would be off. But the cycling through the night was enough to wake up to a dead car.
Be careful continually jumping the car as I believe this reduces the battery cycle life
Be careful continually jumping the car as I believe this reduces the battery cycle life
Safety Car
Joined: Aug 2013
Posts: 4,427
Likes: 604
From: Minneapolis Mn
A simple test would be to drive the car as you have, disconnect the battery once done and leave it overnight as you have in the past. Once that timeframe is done, rehook up the battery and see if it will start or not. If it starts, then it's likely not the battery but rather an electrical draw that is causing your problem.
If it's something drawing current then it will take more work IMO. If you have a multi-meter that can measure amps, with everything off measure between the negative cable and battery and see how much draw you have. Then you will have to work through them one circuit at a time.
Another tool I found is this one I've attached the picture of. You take out a fuse from the panel, plug in the meter and plug the fuse into the meter. It will show how much draw is on any circuit at any time. I got this one at HF but I've also seen them on Ebay.
Hope that helps. Good luck
If it's something drawing current then it will take more work IMO. If you have a multi-meter that can measure amps, with everything off measure between the negative cable and battery and see how much draw you have. Then you will have to work through them one circuit at a time.
Another tool I found is this one I've attached the picture of. You take out a fuse from the panel, plug in the meter and plug the fuse into the meter. It will show how much draw is on any circuit at any time. I got this one at HF but I've also seen them on Ebay.
Hope that helps. Good luck
Le Mans Master
Joined: Dec 2005
Posts: 8,561
Likes: 945
From: Communist Colorado
It is my belief and opinion that when there is an issue with one part of a system, all parts of the system should be checked and tested. The possibility exists that there can be more than one issue happening at the same time.
Im not saying there isnt a parasitic draw.... its entirely possible. I just like checking the basics before delving deeper.
When I was turning wrenches as a fleet mechanic years ago, Ive seen several times where corrosion has built up actually inside the battery cable, under the vinal jacket. Cables are a basic but extremely important part of any 12v charging system.
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Thread Starter
Drifting
Joined: Mar 2017
Posts: 1,897
Likes: 164
From: Nashville TN
2017 C4 of Year Finalist
Supposedly it was tested good so ASSUMING that it was load tested and not just 12V across the terminals, it might be ok. I suppose a way to eliminate the alternator is to trickle charge it overnight, disconnect terminals and see what happens. If it is the alternator, why does it work perfectly after it has been jumped?
I have deleted my cold start injector, so it takes a little more cranking to actually get the car started in the morning. However, it only cranks once or twice before it stops and just starts clicking-I think it should crank a few more times before clicking.
The starter COULD be an issue-except that it starts RIGHT up when it's charged. Are you thinking the starter is drawing too much current? It's pretty old, looks like it might be original to the car, so 30 years?
I did run out this morning and try something-I disconnected the positive terminal of the battery, then tapped the positive wire to the positive terminal-there were quite a few sparks (more than if you were to hook up jumper cables, for instance) when I did this. Maybe my logic is flawed, but unless something is drawing a decent amount of current, there should not be sparks, right?
Racer
Joined: Apr 2016
Posts: 335
Likes: 93
From: San Antonio TX
I did run out this morning and try something-I disconnected the positive terminal of the battery, then tapped the positive wire to the positive terminal-there were quite a few sparks (more than if you were to hook up jumper cables, for instance) when I did this. Maybe my logic is flawed, but unless something is drawing a decent amount of current, there should not be sparks, right?
Safety Car
Joined: Aug 2013
Posts: 4,427
Likes: 604
From: Minneapolis Mn
Courtesy light, alarm system, if your radio has a clock or retains stations, any add-ons can all draw some power.
I suggest undoing the negative cable rather than the positive cable first. If you accidently touch a wrench to frame, one will arc (the positive cable) while the other one (negative) won't.
I still say find out now many amps you're drawing when off. That's a starting point to try and figure out what's going on.
Thread Starter
Drifting
Joined: Mar 2017
Posts: 1,897
Likes: 164
From: Nashville TN
2017 C4 of Year Finalist
Courtesy light, alarm system, if your radio has a clock or retains stations, any add-ons can all draw some power.
I suggest undoing the negative cable rather than the positive cable first. If you accidently touch a wrench to frame, one will arc (the positive cable) while the other one (negative) won't.
I still say find out now many amps you're drawing when off. That's a starting point to try and figure out what's going on.
I suggest undoing the negative cable rather than the positive cable first. If you accidently touch a wrench to frame, one will arc (the positive cable) while the other one (negative) won't.
I still say find out now many amps you're drawing when off. That's a starting point to try and figure out what's going on.
Good point on the negative cable-I DID manage to arc it once today.
Safety Car
Joined: Aug 2013
Posts: 4,427
Likes: 604
From: Minneapolis Mn
Yes you can arc touching the negative to battery but won't arc if you touch the wrench on the cable to the body somewhere. Nothings perfect but some are less risky than others.
Le Mans Master
Joined: Dec 2005
Posts: 8,561
Likes: 945
From: Communist Colorado
Have you checked all the battery cable connections? If your battery is good as you say, as is your alternator, and the starter starts right up... maybe loose connection at the starter. S terminal of the solenoid could also be loose or corroded.
Is the battery at 12.7 volts after sitting all night? Thats a fully charged battery.
Measuring anything by the amount of sparks is ludicrous at best...
Is the battery at 12.7 volts after sitting all night? Thats a fully charged battery.
Measuring anything by the amount of sparks is ludicrous at best...
Thread Starter
Drifting
Joined: Mar 2017
Posts: 1,897
Likes: 164
From: Nashville TN
2017 C4 of Year Finalist
Thread Starter
Drifting
Joined: Mar 2017
Posts: 1,897
Likes: 164
From: Nashville TN
2017 C4 of Year Finalist
Have you checked all the battery cable connections? If your battery is good as you say, as is your alternator, and the starter starts right up... maybe loose connection at the starter. S terminal of the solenoid could also be loose or corroded.
Is the battery at 12.7 volts after sitting all night? Thats a fully charged battery.
Measuring anything by the amount of sparks is ludicrous at best...
Is the battery at 12.7 volts after sitting all night? Thats a fully charged battery.
Measuring anything by the amount of sparks is ludicrous at best...
I doubt it's a starter connection issue. Jumping it starts it right up. The battery is going dead-whether that's because it's a bad battery, or because there is a parasitic power drain, is the issue to solve.
Zen Vet Master Level VII
Joined: Mar 2016
Posts: 5,218
Likes: 1,174
From: Southlake, TX
I feel your pain. I changed out the battery for a new one today. All of the sudden the engine cranked real S L O W L Y and then not at all. I got a 12.2 on the test gauge, but you just know it drop to zip during a cold crank.
The battery was made in August of 2009 so I swapped and started right up.
Sometimes its the obvious. Don't fight it.
The battery was made in August of 2009 so I swapped and started right up.
Sometimes its the obvious. Don't fight it.