Can you solve and argument?

jadefox

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Ok, so hubby and I have had an argument this morning as I feel like there is something wrong with the battery on the car, and I feel like a low battery will make a difference on the performance of the car.

A little history; there has been a few times recently when some of the electrics have played up a little - silly things like the key fob taking about 5 attempts to open or close the car, the electric windows messing about etc & then the other day I was sitting in it with the engine just on the ignition lights, but the command was on, I'd just had a 5 minute phone call, and the heated seat was on, and all of a sudden the command said - "due to lack of battery power this unit will shut down within 3 minutes" I then tried to turn the engine over and it was dead, took the key out, phoned the AA and by the time I had got back into the car, it decided it would turn over! As I drove it off from that incident it sounded like a tractor - was slow to pick up and basically sounded like it was really p!ssed off lol :crazy:

When we got in it today (I was driving) the engine took ages to pick up - the acceleration was sluggish and the performance was bad until we'd been driving for about 10 minutes.

He said the performance of the engine has nothing whatsoever to do with the battery. I disagree.

I think that the newer engines are power hungry and they will naturally draw more from the battery, so if your battery power is not at full capacity, it stands to reason that the cars performance will be effected? :dk:

Can any of you superbly intelligent people tell me if I'd barking up the wrong tree (in which case I'll have to admit that Mr Jadefox is right! :rolleyes: )
 

BaldGuy

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My guess is that "Mr Jadefox" is going to have a lovely dinner cooked for him with a cheekly little red and "Mrs Jadefox" will be having some humble pie for dinner.......
 

flango

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2 definite schools of thought on this one but some interesting theories put forward HERE bear with it as it's not exactly easy reading :)
 

Stratman

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The battery is for starting the car. When the engine is running the alternator provides all the power the electrical consumers need, and recharges the battery. Occasionally when there is an exceptionally high load on the alternator (like when the headlights, heated seats, heated rear window and suchlike are on all at once) and the engine is idling, it may not be able to provide sufficient current and the battery will make up the shortfall. Once the revs increase the alternator once again will be able to provide all the power necessary. This won't have any discernable effect on the engine's power, and it certainly wouldn't account for the rough warmup.

Get ready to bake some humble pie :D
 
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jadefox

jadefox

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But, my argument is, in modern engines, surely you would lose horse power (maybe only a little bit - but enough to make a noticeable difference?) if the battery is drained - or more accurately not totally healthy?

Whatever the case, if the battery is weak, surely it puts out less of a spark in the combustion chamber. :dk: Wouldn't that mean that not as much fuel is burned and if it is, not being burned as efficiently?
Surely loss of combustion and efficiency could easily lead to diminished performance?
 

BTB 500

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Umm ... haven't you got a diesel? No spark plugs ...
 
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jadefox

jadefox

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Well that just blew that argument out of the window - thanks Bill ;)

I just went on the link the other poster put up - and it does seem like it can make a bit of a difference - but not enough to convince my hubby that I am right probably lol
 

whitenemesis

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Erm, you drive a Diesel .. There are no spark plugs to spark.

Too slow .... :(
 
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davidjpowell

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Are you sure it's not the temperature now it's getting a bit colder again? (well it is up here!)

I got in ours yesterday, and found it hanging onto gears, sluggish and noisier just as you said. As soon as it was warm, it was normal again.
 
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jadefox

jadefox

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Yes, you are almost certainly right, it probably is the temperature - but I just thought it was odd that the car had given it the large one the other day about the battery being low - so I kind of put two and two together. :eek:

I'm getting a bit fed up of these random electrical faults. They seem to just come and go - one day the cruise will be working, the next it's broken, then it comes back. The windows wouldn't auto shut - then they were fine. The key fob keeps messing around and now this odd battery warning thing.....it's all a bit much :crazy:
 

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Could low system voltage on a newer model not cause it to go into 'limp mode' until battery fully charged and reset ( stop/restart ) ?
 
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jadefox

jadefox

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Could low system voltage on a newer model not cause it to go into 'limp mode' until battery fully charged and reset ( stop/restart ) ?
Will be interested to hear any theories on if this is possible.....just so I DON'T have to eat humble pie :eek:
 

Howard

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Starting with the obvious , have you had it on a STAR to see if there are any obvious faults ?

SAM packs ?

24/7 drains even with ignition off ? sometimes when these packs fail , they can go open circuit and then there is a permanent live , which kills your battery ...

How old is the battery ? is the original one ?

First thing is to get it on a STAR and test the packs.
 
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jadefox

jadefox

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We did have it on a STAR when it first started messing about and nothing came up :-/

Oh, no wait, I think a spark plug fault might have come up....... :D :p

The mechanic was at a loss to know what was causing these irritating faults so we just left it.
It's not all the time which is the most frustrating part - I wondered at one point if the fuses were getting a bit damp - and we re insulated the main wire loom which runs from the fuse box just in case moisture was getting in. The problems have been less than before we did that I have to say.

The battery is the original I believe yeah.

The odd thing was, it told me it was going to turn off the command because of insufficient power, then it wouldn't start for about 5 turns of the key - they bingo - it started and hasn't done the same since! Thats the worst part - if the darn car broke at least I'd know what it was that was causing it!
 

Howard

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Can you get it to Ollys one day ? I'm sure he would be able to sort it.

These intermittant faults are a nuisance aren't they ?

Anyway , why aren't you at the cooker , the pie won't cook itself .... ;)
 
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jadefox

jadefox

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Haha - oh stop it - i am actually right I think you'll find. Point being that I was arguing on the theory of petrol engines and the way they work - just because I have a diesel doesn't mean i'm wrong - technically I am right - so there :p lol
 

AMG-Al

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Yup, that was just what I was about to say.

A woman who is totally wrong is usually 100% right............. :(
 

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