My car will run if i charge the battery but if it sits for a while it will not start

Diagnosing Common Automotive Charging System Problems

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Sep 18, 2013 - If your vehicle is already dead, jumpstart the battery and wait. ... If voltage is below 13.5, there's a good chance the alternator is not keeping ... Problem: Dim lights or lights that seem to fade as the car runs. ..... I replaced the battery and thealternator, the truck is running fine but the battery light is still on and ...

Not starting after leaving it sit over night - CarGurus

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CarGurusApr 28, 2014 - Not starting after leaving it sit over night - I have a '99 mercury grand ...it acts like the car is dead for days at a time and will not start again ... Battery is goodand so is alternator. ... But it still starts if I switch out the starter relay.

Why My Car Won't Start? - Reasons and Solutions

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Battery seems good, the engines cranks but car won't start. Removed #1 plug ... Still no spark and my car won't start, please help. Answer: For ... Your alternator might notbe charging your battery the way it should or you could have a faulty battery. Most auto... Two days ago the truck died and nothing would work. It wouldn't ...

Auto,Car,truck Won't Start, diagnostic help, start test, advice

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BATTERY IS WEAK FROM SITTING,JUMP IT AN TAKE IT FOR A DRIVE TO CHARGE BATTERY BACK UP,MY TOYOTA'S BATTERY USED TO GET WEEK WHEN I LET IT SIT FOR 2 WEEKS.i F YOU LET IT SIT .START IT EVERY 3 DAYS TO KEEP BATTERY CHARGED.

I'm not certain I understand the problem, but it sounds as though the battery is not charging properly. Check it yourself, or have the charging system and battery checked. With the engine running the battery voltage should read about 14 volts. If it is much lower, the charging system is not working. If the battery goes down with the car just sitting, there is something drawing more current than it should. Easy things to check are for a glovebox light, overhead light, trunk light or underhood light that does not turn off. Normal draw with everything off, after sitting a few minutes, should be less than 100 milliamps. I hope this is helpful.

Have your battery load tested at auto parts store. Do it while still in the car. They can also check your alternator at the same time. It sounds like you either have a short that is draining the battery as it sits overnight or as your vehicle runs the battery has enough charge to run but not enough charge to last it UNTILL the next morning.

This problem may be a drain or a bad battery or alternator.

The first thing to do before going on trying to find the system that is draining the battery would be to have the battery tested and charging system tested.

A weak battery will seem ok after the car is jumped or will barely start the car and the alternator will charge it even though the alternator is overworking due to weak battery and during the day or when car does not sit long it will seem ok. then when car sits overnight or a few days battery will weaken on its own, making it look like a drain,

so first step is battery test and alternator/charging system test.

You never jump a dead battery
That is an unsafe act and could
result in an explosion

You must charge any battery fully,
to start any diagnostic proceedure

You never remove either battery cables,
while a vehicle is running,another practice
that will bite you sooner than later

It sounds as though the battery is not
capable of taking a charge and offers
too much resistance to run the car hooked up

IF IT DRAWS DOWN WHILE SITTING OFF U SHOULD HAVE SOMETHING DRAWING POWER IF SO DISCONNECT CABLE WHILE IT SITS RECONN WHEN READY TO START IF U HAVE JUICE TO START THEN SOMETHING IS DRAWING CURRENT TRUNK LIGHT AMP SHORTED SWITCH ETC!! HOPE THIS HELPS!!

Take the battery in and have it tested to make sure it is fully charged and is holding that charge and that all the cells are good....letting a car sit for any length of time without starting it and letting it run for a bit is bad news. Batteries will go bad. Gasoline left to sit in a car will "go bad" and can leave a coat of varnish on sensitive injectors, fuel lines, etc... Water and debris can ruin the fuel filter. Check the battery first, put some injector cleaner in the gas tank and you may also want to spray the throttle body with a recommended cleaner before trying to start again. It may also help to pull your spark plugs and clean or replace them. Hope this helps. Good luck.

the alternator is not charging and once you run out of battery power car dies when you let it sit battery builds a small charge enough to run short period of time.get charging system checked.

replace your battery, a battery discharges every day you dont run the alt. to charge it up... after a week or 2 weeks the battery would be dead, just from a car sitting not being started... if you are not using the vehicle, it is a good thing to replace the battery, and every couple days just start the car up and let it run a while to charge the battery.... if you are going to have to leave the car for a while without starting it, then disconnect the battery, and remove it from the vehicle... you can buy a cheap trickel charger for the battery when it is out that will keep it charged till you decide to put it back in.... hope this helps you...