# Car won't start after sitting for 3 weeks **URL:** \ **Category:** Maintenance/Repairs\ **Created:** [August 9, 2007, 2:51am UTC](https://community.cartalk.com/t/car-wont-start-after-sitting-for-3-weeks/2839 "2007-08-09T02:51:25Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![Hushpuppy](https://avatars.discourse-cdn.com/v4/letter/h/a183cd/32.png) [@Hushpuppy](https://community.cartalk.com/u/Hushpuppy)\ **Post date:** [August 9, 2007, 2:51am UTC](https://community.cartalk.com/t/car-wont-start-after-sitting-for-3-weeks/2839/1 "2007-08-09T02:51:25Z")
Netizens, My 1990 Honda Prelude with the 2005 Sears Diehard Gold battery wouldn’t start after sitting for 3 weeks. Jumping it got it going right away. My ammeter shows that at idle, the alternator is supplying 7 amps of current to the battery so I don’t think I have an alternator problem. But I drove the car for a few miles after jumpstarting it. After letting it sit for a couple of hours it wouldn’t start again. Is my battery dying, or do I need to buy a charger to keep it juiced up if it sits for a few weeks? (the clock and radio draw a couple dozen mA continuously) Thanks. ---
**Author:** ![wentwest](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/wentwest/32/6073_2.png) [@wentwest](https://community.cartalk.com/u/wentwest)\ **Post date:** [August 9, 2007, 3:21am UTC](https://community.cartalk.com/t/car-wont-start-after-sitting-for-3-weeks/2839/2 "2007-08-09T03:21:20Z")
You need to clean your battery terminals. ---
**Author:** ![hellokit](https://avatars.discourse-cdn.com/v4/letter/h/6a8cbe/32.png) [@hellokit](https://community.cartalk.com/u/hellokit)\ **Post date:** [August 9, 2007, 4:00am UTC](https://community.cartalk.com/t/car-wont-start-after-sitting-for-3-weeks/2839/3 "2007-08-09T04:00:50Z")
Agreed. Disconnect the battery cables. Using files, sandpaper, penknife, etc, clean the cables and battery posts. ---
**Author:** ![Joseph\_E\_Meehan](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/joseph_e_meehan/32/21_2.png) [@Joseph\_E\_Meehan](https://community.cartalk.com/u/Joseph_E_Meehan)\ **Post date:** [August 9, 2007, 10:47am UTC](https://community.cartalk.com/t/car-wont-start-after-sitting-for-3-weeks/2839/4 "2007-08-09T10:47:10Z")
What was the voltage at the battery with the engine running? 7 amps is only 84 watts, not very much; that won’t even cover the headlamps. ---
**Author:** ![mcparadise](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/mcparadise/32/32_2.png) [@mcparadise](https://community.cartalk.com/u/mcparadise)\ **Post date:** [August 9, 2007, 11:09am UTC](https://community.cartalk.com/t/car-wont-start-after-sitting-for-3-weeks/2839/5 "2007-08-09T11:09:53Z")
I suggest having the battery and the charging system tested. Many auto parts stores will do this free. If you need to leave the car sitting for weeks at a time, consider a Battery Tender, which will keep the battery charged without overcharging it. ---
**Author:** ![Hushpuppy](https://avatars.discourse-cdn.com/v4/letter/h/a183cd/32.png) [@Hushpuppy](https://community.cartalk.com/u/Hushpuppy)\ **Post date:** [August 10, 2007, 8:15pm UTC](https://community.cartalk.com/t/car-wont-start-after-sitting-for-3-weeks/2839/6 "2007-08-10T20:15:51Z")
Thanks for the replies. I’m going to clean the terminals, although I don’t think that’s it- but you never known. For two reasons: 1. They look clean (I know, it’s the corrosion inside that counts… but they’re not corroded like in days of yore), 2. I messed with the cables and there’s been no change in behavior (in the past when I screwed around with cables, and they were the problem, something always changed). By the way, I measured current at the battery… the 7 amps was only the flowage into the battery itself. The alternator was still supplying current to the rest of the car, too. How much? I don’t know… I didn’t measure the rest of the car. But 84 watts being pumped into the battery sounds like a goodly amount of juice, and doing it at idle sounds like there’s plenty of the electrons to go around. If the battery was healthy I don’t think I’d want that much being pumped into it on a continuous basis. I’m wondering how the charging system could be at fault. The battery tender is an excellent idea. -the Pupp ---
**Author:** ![Cougar](https://sea1.discourse-cdn.com/cartalk/user_avatar/community.cartalk.com/cougar/32/21348_2.png) [@Cougar](https://community.cartalk.com/u/Cougar)\ **Post date:** [August 10, 2007, 9:08pm UTC](https://community.cartalk.com/t/car-wont-start-after-sitting-for-3-weeks/2839/7 "2007-08-10T21:08:13Z")
It isn’t a good thing to let the alternator charge up a drained battery since it puts a lot of demand on it. If you have a battery charger I recommend you use it to charge it up and then have the charging system checked out along with a load test on the battery. I would also have the shop check for a parasitic current drain while the car is parked. You may have a problem there.