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Discussion Starter #1
For the last few weeks I've only been using the car once every 10 days or so, and every time it's left the battery goes completely flat and needs charging. It will then be fine untill I leave it for say a week, and then it will be flat again. This was never a problem when I used the car regularly, so would this indicate a fubared battery?
 

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Discussion Starter #2
I should also add it does this even when I disconnect the earth from the battery proir to leaving it, so that rules out a current drain.
 

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go into your local halfords and ask them to test the battery for you. they have a hand-held terminal that gives a read-out to say whether the battery is fubar'd or not.
 

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Discussion Starter #4
Well funnily enough I was trying to bump start the thing the other day in a petrol station forecourt, and a bloke came running up with a battery booster to help me out. He asked me what was wrong with it and I told him I suspect the battery goes flat becaue I don't use it enough. He had a load of gismos on him too which he tested the battery with and told me it was actually a problem with my alternator. But a dodgy alternator wouldn't cause the battery to drain flat when not even connected would it?
 

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the alternator charges the battery when the engine is on. if the alternator is knackered then it can't charge the battery, simple.
 

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Discussion Starter #6
It discharges when the car is left standing. The car is fine when used regularly, but if I leave it for just a week, even with the battery disconnected, it will be flat.
 

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Ed said:
For the last few weeks I've only been using the car once every 10 days or so, and every time it's left the battery goes completely flat and needs charging. It will then be fine untill I leave it for say a week, and then it will be flat again. This was never a problem when I used the car regularly, so would this indicate a fubared battery?
This happend to me too.
Answer: buy a new battery.

Most batteries only last 3-4 years, no matter what sort of gurantee you get with them. bought a Cav diesel battery from Halfords for £60 which solved the problem, I can leave it for a month and the car will still start.

For more info on car batteries, see my guide at

http://www.topbuzz.co.uk/info/car_battery/car_battery.htm
 

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when u mention using it regularly, do u use it on many occasions during one day or few occasions over a period of days?
still think it's the battery, get a 2nd opinion
 

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It could be the alternator. If the voltage output has dropped a bit, or it's current is limited in some way, then the battery may be charged enough to start the car for a while, bit will quickly drain away.
Try and measure the voltage with the engine idling, rad fan and any big electrics off. Should get just under 14V, up to 14.5 is fine. Anything more than this could be damaging the battery. If the voltage drops below 12-ish volts when you start to turn things on, the battery will no longer be charging.
In this instance, you will need a new battery wither way. Let a car battery go flat more than a few times and it's knackered.
 

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Discussion Starter #12
Oh joy. Yet more money needed to fork out then. Any suggestions for which battery I should get. People rave about the Diesel ones don't they?
 

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> People rave about the Diesel ones don't they?

Its beacause they have a very high cranking amps.
So they work well in the cold.

If you read my guide they temperture only needs to to freezing and the battery is only 35% efficent (or something along those lines), even on a fully charged battery. So when you leave your car outside over night, and there was a cold snap, chances are it won't start.

Plus diesal batteries have a bigger capacity, hence why they are physically larger.
 
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