I’m interested to know how long we think a modern car will be able to sit for, before the battery starts to get a bit low?

For context, I have a 2020 Octavia. The battery is just under a year old. Start/Stop is nearly always deactivated and the battery was at (I assume) a full state of charge.

I last drove the car 10 days ago (2hr motorway journey) and it has sat on the driveway since. By the time I drive it again (I’m busy with work) it will be the end of the week - just over two weeks since it was last driven. I’ve been in it once, to unplug my CarPlay adapter and rescue my sunglasses.

I’m interested to know two things. A) I’d like to know how long can the car reasonably sit for, before the battery starts to get low? And B) how long can the car sit for before damage to the battery starts to occur (due to discharge)? Bearing in mind, it’s summer now, not winter.

I would hope to see what, three weeks before it gets low, and a month plus before damage starts to occur? Is it worth plugging it in to a charger, or for two weeks is that overkill?

I know I should probably charge it, but the engine bay has no suitable ground, and I haven't got time to find one. I also don't fancy confusing the car by charging it with the negative connected to the battery, as for only two weeks this seems overkill?

@nta16

Edited 10 August, 202510 Aug by OccyVRS

Lots of variables on this but if the battery was in reasonable state of charge and health before you parked it up and you've not left anything plugged in so just the usual car draining then I'd not worry about two weeks. Have a look in your 'Owner's Manual' for where the negative post is in the engine bay and it might say something like disconnect the battery if you're not using the car for 3(?) 4(?) weeks.

Damage due to just sitting would be a very long time and again be dependant on variables but bear in mind letting the battery get too low and/or for too often then there will be an accumulative effect and recharges might not get the battery to fully how it was before.

Also bear in mind the 12v likes say 20c ambient and self-discharges IIRC twice as much at 30c and twice as much again at 40c so even if disconnected this is a factor but of course so far we don't have too many days at 30 or 40 (IIRC 40.2c near me a couple of years ago). The VWŠkoda stop/start car battery charging is said to keep the battery to 80% charged to allow 20% headroom for regenerative charging during braking.

You also need to consider some people use (and waste) more electricity in their cars (and homes) than others and their driving and journeys can vary a lot, the use, if required, of an appropriate charger maintainer following the instructions in the car's 'Owners Manuals' and charger maintainer for recharging the battery has got low or too low (or perhaps preventative charging by driving or use of appropriate charger maintainer).

Unfortunately for some with expanded egos and/or testicles larger than their brain it's an afront against them and/or machismo to read instructions.

On a battery this young easiest thing to do is use a multimeter on the battery terminal posts a good few hours after the car has been driven and note the reading and do the same again one, two, three weeks later and see if the battery has dropped much - this of course isn't a complete picture as our chap from down-under will point out but unless you've really hammered the battery with use, abuse and neglect it's good enough.

Edited 11 August, 202511 Aug by nta16

From the 2020/07 'Owner's manual' - see last line, "for more than three weeks".

Engine bay earth point. If you have an appropriate charger maintainer and the facilities you can leave it connected up so that it rechargers the battery and then maintains it at that level ready for the next use of the car. The battery and car's charging system are designed for cyclical use so personally I'd never leave the maintainer on for months on end as cars need use for keep other systems, components and parts working well. If I couldn't use the car for whatever reason after a month with the maintainer on I would disconnect it for a couple of weeks before putting it back on. If the car isn't used for many months I'd consider selling it.

HTH.

Thank you, Nigel - I appreciate it!

That's much in line with what I was thinking. Of course, one interesting thing I've realised is that the age of the car, really, doesn't matter much. An older car will have a smaller battery, but will have about two electrical things in it. A new car will have a much larger battery (start/stop aside), but will also have seventeen computers running 24/7. I would imagine with KESSY and the like, this will be even worse.

The other consideration is that the alternator on a new(er) car doesn't seem to charge the battery all of the time when the car is moving. It sticks to around 80% as you say, but there are other variables too.

I'd never had a battery go until the Octavia died last September, and it was an utter nightmare finding a new one and getting it coded in before a trip - not to mention the cost.

Thank you for the information regarding the earthing point - I'm not sure why I didn't remember this. As you say, I should read the manual!

From memory, I have the following charger. It will do the job, however I might take a walk to Halfords tonight and see what CTEK stuff they have - we're finding the BMW sits in the garage for longer periods, and with it being KESSY it might make sense to charge it between uses. A few hours (say five or six) will suffice, surely?

For those reading this - if your car has an AGM battery (like the BMW does) then you will need a charger without a desulphation mode - this can damage an AGM batter (and isn't great for an EFB battery either).

I'm saying this as the most popular CTEK charger, the MXS 5.0, charges at above 15V at various parts of the cycle, which isn't great. The CTEK CT5 (that I'm about to buy) doesn't have a desulphation mode, and charges below 15V.

https://www.ctek.com/uk/battery-chargers-12v-24v/ct5-start-stop-uk?srsltid=AfmBOor6LTCZI083FGI6Z_N-ZvKD1bFGvF1Uhd_bhOf3fIvYG2PVwJ3m

Think of the battery and alternator as working partners if either is low or poorly the other has to do more work so will to some extent wear more so shortened life. So an old worn battery will have the alternator working more perhaps and a new battery in a car with an old worn alternator will have the battery doing more.

7 minutes ago, OccyVRS said:

From memory, I have the following charger. It will do the job, however I might take a walk to Halfords tonight and see what CTEK stuff they have - we're finding the BMW sits in the garage for longer periods, and with it being KESSY it might make sense to charge it between uses. A few hours (say five or six) will suffice, surely?

Halfords never knowingly under-priced. 😄 The previous one looked like my Ring charger (but more expensive) so does that one that'll be fine for your BMW, no need to spend more money on a CTek, unless you want to.

How long it takes to fully charger the battery depends on many things but as I've put you can leave that Halfords (Ring?) charger maintainer as long as you like. - "Designed for long-term charging".

5 or 6 hours may or may not be sufficient to sufficiently recharge the battery or to fully (as much as possible) recharge, it depends how low the battery is at the start and how much drain there is in and on the car. 4-amps is lowish so takes longer to charge the battery but low amps is good for recharging, especially a battery that has discharged slowly.

When you connect up the chargers positive and negative clamps/leads and then plug int the electric mains supply the charger maintainer will light up and then give a voltage, from that you decide if the battery needs charging or if you want to. You could connect up the charger maintainer every time you park up if you want to but there's no need to overdo things, or get paranoid about the battery. Whilst charging the battery is very easy, clean-hands 'work' it's still farting about on a car which you want to keep to a reasonable minimum as just about most other things are better and more rewarding in life.

I do enough with the battery on my wife's Fabia to give it a reasonable long life as they're expensive and I expect decades rather than years out of stuff I buy and much, much more importantly that it doesn't give my wife any hassle on the car as that means a lot more hassle for me farting about even more with a car I don't like and I loathe working on our cars. This is why I replaced the battery as I learnt what a PITA these modern VWs are, not that I've ever liked VWs, or German cars generally really, except perhaps a Golf MK1 GTi and I did consider a BMW Z4 and Alpina Z4 for a very short time (s/h). VW rant over.

If you want more battery or VW stop/start info just ask as I could probably overload you with the very little I've got so only give you what you want. The information is generally fairly easy to find I'm only acting as a librarian and from decades of experience of helping out neighbours with their car batteries from extreme or nil car use.

4 minutes ago, OccyVRS said:

The CTEK CT5 (that I'm about to buy) doesn't have a desulphation mode, and charges below 15V.

You can of course do as you please but I'd be surprised if your Halfords charger maintainer isn't suitable for AGM batteries, check the manual.

Things aren't as black and white as they are sometimes presented, many differences in models and their "features" and functions can be more about marketing and sales of the charger maintainers.

ETA: there's not going to be much de-sulphation with most ordinary car use or occasional short term non-use.

Just as an example, I and others, have replaced an EFB battery in the engine bay of a VWŠkoda with an AGM battery without adding the extra required heat insulation and use standard "smart" (they're not, no "smart" devices are) battery charger.

Now I'm not saying anyone else should do either particularly if they are worried about it and/or don't want to but so far in four years of the AGM battery being fitted and say three years of it being charged with the standard "smart" charger maintainer (whilst in the car) the battery seems fine and certainly hasn't melted or blown up, if it packs up within the next 2 or 3 of years or so (at 6 ,7 years old) I'll know I got something very wrong.

Edited 11 August, 202511 Aug by nta16
ETA

I decided to go ahead and pick up the CTEK CT5 Start/Stop charger. The Halfords one has seen some use, and frankly, I think my girlfriend could do with having it.

It's not so much that the charger 'can't do' AGM batteries, but rather the desulphation mode (basically large pulses of current) that most chargers have on every cycle, aren't great for AGM batteries. That said, it claims it is for LiFe4Po batteries and Lead Acid, and doesn't actually mention AGM. The EFB+ in my car is just a fancy LA, mind.

I don't intend to use it on my car very often - although, of course, in a scenario like this, it's probably quite handy to have. The BMW belongs to my dad, and I've no interest in giving him a charger that might affect his battery negatively. Given the price of a new battery, I don't think £79 is an unreasonable amount to spend on a charger - especially if it will see use for 24-48 hours every month. When I walk into the garage, I can hear his car doing things, so I've no idea if the sensors are active or what. I know if the engine is hot when it is parked, the grille is open, but then once it is cooler, the grille shuts. All of that must drain the battery!

It's coming tomorrow with Amazon, so I'm going to just plug it in and leave it. My car is a Mk3.5 (it is a 2020, but the manual for it seems to be 2019/07) however the process with regard to positive terminal on battery, then the earthing point for the negative, seems to be the exact same. Of course, this keeps the cars electronics in the loop, so it knows what is going on.

Dad's car is in the garage so can be left until done, however the other two live on the driveway. If I plug my car in, and by say, 9pm it still isn't fully charged, surely I'm able to just disconnect it (unplug from wall, disconnect negative then positive)?

I also saw adapters that enable the battery to be charged via the 12V socket in the car. I didn't pick one up, but I thought it was an interesting idea.

Thanks again for the help - I understand batteries to some degree (I used to make my own LiPo batteries), however Lead Acid/AGM batteries and cars, are not something I've had endless experience with.

It does all seem a bit of a faff, but balancing an £80 charger and fifteen minutes of time in exchange for a healthy car and lack of a £300+ battery replacement bill seems to be a reasonable trade.

As a family, we used to only have one car - a 2011 A3 Sportback. I was in school, dad would work in town, so only mum needed a car. We bought it new in 2011, and dad only got rid of it over Easter. In the whole fourteen years of ownership, the battery went once. I'm wondering if new(er) cars are more prone to battery issues, due to the electronics in them? Certainly, I don't remember old(er) cars having as many battery-related problems.

Has pulse charging actually been proved to do anything different really then, pulse charging was more marketing buzz last time I looked it up many, many moons back now mind.

I'm not sure the £75 is 5 times as good or will last 5 times as long as the £15 and unlike my mate if you only have one Ctek you won't see inconsistences with a second same model.

For your Dad's BMW do check and read the 'Owner's Manual' and check if there one or two 12v battery(ies), even the old ones had points in the engine bay for neg and pos as the (single) battery is in the boot under a silly fragile power points bar so a PITA to even see let alone really get at.

Amazon isn't the only suppler in the world (and not often the lowest priced) but it soon might be if no one shops elsewhere.

If you can't fully recharge in one go you can try more goes, as Tesco tell us every little helps. An outside double mans socket is very handy for lots of things (I've only a single at the front "garden").

If using a 12v socket you must check that it can be used for charging.

The Ring, Halfords, CTek charger maintainers also have O-ring terminals to add a permanent connection on to the battery or you can make up your own leads and connector.

£300+ ! Are you looking at Amazon prices for batteries too !?! 🙂 And 15 minutes would be going slower than me and I never go at any pace working on a car, that would include going to the shed, remembering where I left the charger, betting it out of the box, walking to car, forget car keys, going back for car keys, connecting up, untangling wires, plugging in, waiting for reading, pressing mode watching to see how quickly the volts reading goes up, walking away. Yeah, perhaps 7 and 1/2 minutes - but you might have a much bigger property than our very small place.

The battery wouldn't have been at fault, it would have been your Dad forgot about he battery because it's so reliable the same as now. Just think of the battery like a bank account if you don't want it in the black (empty) or too low then you need to put in at least as much as you take out to retain what was there before but time will diminish things anyway (inflation as battery age, abuse and neglect), hope that makes sense.

Imagine if you had a slot card meter to for the electric used in the car you'd soon learn about usage, same way you do when you pay for home electricity rather than your parents, you don't leave stuff running than doesn't need to be as much.

😄 2011 is still a new car to me, newest car I've ever owned was in 2004 and I only kept that for about 6 months. 😄

Yes - seemingly charging above 15V is not good for an AGM battery. it's also worth noting that (from my understanding), technically you desulphate a battery every time you charge it.

I believe it's just the one battery in the BMW, but I will definitely check. Amazon isn't the only supplier, and normally I loathe to buy big bits from them - however the Halfords near me have nothing suitable and Amazon just so happened to be the cheapest/easiest with regard to price and postage. I always prefer to go independent and have an item in my hand - however needs must, and I don't have the time this week to be hunting around decrepit auto parts stores for a decent charger!

I have a fancy ratchet/clip set of connectors for 12V batteries - I used to use car batteries to supply power for model jet engines.

I was in a pinch for replacing the battery, and a genuine 000 915 089 AC battery (with the VW stamp, made by Moll) was a hair over £300 IIRC, with the total bill being nearly £400 after Skoda had fitted it. It wasn't the best solution, but I didn't really have another choice at the time!

It might be slightly larger than yours, however I live in London - so when going about the process of charging the car on the driveway at the front, there are numerous blast doors and risk assessment criteria that must be checked before one can leave the kitchen window open with a charging cable poking out of it 😂

I remember my parents test drove the then new 2012 model - it was the A3 8V and had the pop up screen in the centre console... pretty cool stuff. Dad hated it though, and promptly went and bought the newest old shape he could! I think a lot has changed since then, with regard to electronics. That car was by no means a low spec - in fact, almost every option was ticked (fully electric, heated and cooled, adjustable lumbar leather seats, cream leather interior, full Bose system, surround sensors, etc). Compared to the BMW though, it is stone age - stuff like the digital dash, surround cameras, KESSY (or whatever the BMW version is) and active grille all drain the battery far more than anything on the old Audi did.

Even on my Octavia, if I go and open the car to get something from it, the digil dash and infotainment will wake up for ten minutes or so - that has to be like running two laptops.

I miss my first car, a 2007 VW Fox. it needed either a battery booster or bump start most of the time, leaked fluids everywhere (power steering, coolant and sometimes petrol) and was missing half the interior, but it was so much simpler!

16 hours ago, OccyVRS said:

I’m interested to know how long we think a modern car will be able to sit for, before the battery starts to get a bit low?

For context, I have a 2020 Octavia. The battery is just under a year old. Start/Stop is nearly always deactivated and the battery was at (I assume) a full state of charge.

I last drove the car 10 days ago (2hr motorway journey) and it has sat on the driveway since. By the time I drive it again (I’m busy with work) it will be the end of the week - just over two weeks since it was last driven. I’ve been in it once, to unplug my CarPlay adapter and rescue my sunglasses.

I’m interested to know two things. A) I’d like to know how long can the car reasonably sit for, before the battery starts to get low? And B) how long can the car sit for before damage to the battery starts to occur (due to discharge)? Bearing in mind, it’s summer now, not winter.

I would hope to see what, three weeks before it gets low, and a month plus before damage starts to occur? Is it worth plugging it in to a charger, or for two weeks is that overkill?

I know I should probably charge it, but the engine bay has no suitable ground, and I haven't got time to find one. I also don't fancy confusing the car by charging it with the negative connected to the battery, as for only two weeks this seems overkill?

@nta16

A recent experience may help serve as a guide.

Car - bought new in October 2015 (MY16) Octavia Combi 1.4 TSI, manual 6-speed. 31K miles.

Battery, Moll EFB fitted new in 2016 as a warranty replacement - so battery 9 years old.

Automatic stop/start is always used. I occasionally charge the battery due to frequent short trips (as evidenced by very low miles) The last charge was on June 1st.

Battery was fully charged before trip (Ring RSC608) vehicle was static for 35 days, battery charge state was tested on return from trip and was 53% SAE (12.33VDC) / 66% DIN (12.31 VDC)

Test report was Good Battery but requires charging.

Edited 11 August, 202511 Aug by Warrior193
correction

One thing to remember, even if Stop/Start is deactivated every trip, battery SOC will rarely ever be more than 75-80% charged due to the way the smart charging alternator operates.

Ah the foreign country that is that-there-Lundun with it's strange ways.

I just meant with the charger maintainers unless you let one of the cars get into such a bad way as with your Fox with charging and battery the process will be top-ups and nothing drastic requiring buzz words or "features" just simple rechanging and perhaps maintaining.

The Fox would be a sensible size small car to me and with 50+ years of generally disappointment with computer electronics the less of them the better for me. I like wind up windows!

Warrior's last post is why I always fully recharge the battery on my wife's 2015 Fabia (which really seems to annoy some poster/viewers here) also a 2015 car has less electric features and interfering "assists" than on a 2020 version so less potential drains.

As always each to their own.

You will learn how much each of the cars need recharging, and perhaps preventative charging, by experience (easier with the Ring charger maintainers s as they show voltage figures to learn by rather than just a few coloured lights of the Aldi/Lidl or CTek.

Charging the batteries and keeping them in good order isn't difficult or complex, it's simple or I'd not be able to do it, don't get too tied down by too much details, as I put before things aren't always as black and white as they're made out to be and there's often wriggle room - though it might be forbade in that-there-Lundun tho'.

Good luck.

In all fairness to myself, the Fox came with a knackered battery! It served its purpose well - no frills (okay, air con would have been nice), but was perfectly suited to the use I wanted. In actual fact, it had the most headroom out of any car I’ve owned.

I agree though, the occasional top up is all that is required. I’ve done a lot of driving over the last few years (I haven’t been in London) so we’ll see how my use changes.

I tend to turn off S/S not for the battery, but because I hate it. I don’t like how it’ll stop the engine a minute after a cold start, and I don’t like how it’ll stop the engine every two seconds in traffic when the oil is at 115 degrees. I can’t help but feel it puts so much strain on the engine, all for not much benefit. Equally, for the battery, the starting process is the most stressful thing it does - surely doing it twenty times in one journey really can’t be good for it…

Side note, is there a reason the battery is only charged to 75-80%? I’m aware that fully charging or discharging other (lithium) batteries isn’t good for them (actually, for a LiPo, the theoretical recommendation was between 40% and 80%), however I wasn’t aware lead acid batteries suffered from the same issue?

The reason for limiting the charge to approx. 75% is to allow capacity for regenerative charging under overrun/braking conditions (micro-hybrid)

Actually, provided they are not subjected to overcharging, lead acid battery life is better if they are charged to 100%, due to reduction of hard sulphation of the plates.

Edited 12 August, 202512 Aug by Warrior193

Had you known more about the simple process of charging the battery you might have bought or borrowed a charger and it might not have been as knacked as you thought. It should have least taught you the importance of the 12v battery then and as you're learnt even more so now.

At least you could bump start the car then (but a Fox might well have been a new enough car to have a cat so really shouldn't have bumped it but I would have or better still park on a good slope or hill facing down).

I can't stand a car that won't start, if you can't start the car you can't even limp it home, more difficult to do even that with more modern cars with their computer interferences. I've always wanted to get myself home and sort the car latter as it's only an annoying PITA lump of metal (or metal and plastic with modern German marques) unless it can be driven.

That's why I've always given importance to having a good battery on the car, to start, to power safety items, to be able to diagnosis (the little I can) and sort any starting or electrical problems, and the electronic and computer issues nowadays, I've enough brain-farts of my own without the ones from computers.

When I bought old cars if I was unsure about the battery after brakes and other safety items and checks it would be the first thing I'd change. One car I bought very locally had an iffy battery which had been mentioned but the engine need a good battery to start so when I found how iffy it was as agreed I changed the battery at seller's cost but to be fair I made the mistake of buying a less expensive battery to save the seller money as he'd been fair with me (private seller of course not UK motor trade) and that battery didn't do well so I changed it. What I should have done is asked for £45 as that was the price of the battery like-for-like replacement and said I'd fit the (£70) battery I did later (this was mid-1990s IIRC).

Sorry I thought I'd put about the 75-80^ thing but it must have been in another thread, warrior put it better than me anyway.

I find the stop/start annoying but do think about having the engine turned off to save emissions - particularly when I'm a pedestrian - and more so if a VAG diesel is about! no wonder they're all black!

If you want to know more details about batteries you could have a look at the following, but don't get too carried away about it for your car, I'm often accused here of such but I don't really care that much other than having some reliability with the car and it's such easy clean-hands stuff on the otherwise ancient dirty technology of an internal combustion engined car. - https://batteryuniversity.com/

ETA: 115 is very warm for the oil but a good oil will go to 125 and more anyway before issue, what does the 'Owner's Manual' say about normal oil temps for your car a bit above that I'd guess - but engine oil is another subject and thread entirely - and full of oil believes and debates too. If you have a VRS badge then you probably want better engine oil particularly if you drive in a spirited way the VRS badge was put on the cars for. Second hand with VRS badge can sometimes mean more abused but not necessarily more serviced and maintained by some owners. Have a look at what other well or reasonably serviced and maintained 2020 Octavia run at. Bearing in mind 4 heatwaves so far this summer of course.

Edited 12 August, 202512 Aug by nta16

I normally sit around 95-105 when moving, however when in heavy summer traffic I've seen it get up to 112. Everything is fine though - if I've just hooned it up the A31 and smacked straight into standstill traffic on the M25 in 33 degree heat, I can't say I'm surprised the oil is that warm. That was when the car was putting out just under 350bhp too - it sat very happily for fifteen hours up to Scotland, with rock solid oil and coolant temps. That's my only real complaint with the engine on the vRS/GTI - smaller turbo is fine, but I wish they had a DSG and aux cooler like the more powerful EA888s.

I use Castrol C5 - specifically Castrol EDGE 0W-20 LL IV.

When I get the Octavia I did the tyres, followed by the brakes all round. This year, I've had the DSG done, along with the LSD, plugs, coolant and other bits. Some of it isn't required at the current mileage, but I prefer to do preventative maintenance.

Not actually sure re bumping the Fox, but if I'm completely honest, I didn't care. It was bought for £900 and did a happy 15,000 miles with us as a town car. When we scrapped it for £200, it was actually fixed and driven around for another 18 months. Sadly, now, it looks to be Coke cans.

I'm not knocking you or anyone else, you can have whatever car you like as far as I'm concerned (personally if I only had a choice now of Fox (even £200 fixed) or VRS Octavia I'd go with Fox 9.5 times out of 10, some long boring motorway or dual-carriageway journeys comfort and a bit of entertainment is best). The only VW that has ever interested me was a Golf GTi Mk1 particularly when they were new, near the size of your Fox I'd guess than any Golf from Mk2 on. Plus I'm a shortarse so don't need as much room, but very short legs and long body so do need more headroom than in the back of many coupes or old (70s-90s) Jag saloons.

Don't get too carried away for figures particular PS, HP or BHP, and more so on the speedo. Most often you have far too much more than is needed often only a very small fraction might be used. With heavy German lumps of cars yes you might need a bit more to haul it along and now with modern cars so heavy and with oversized wheels and tyres for fashion sake. The bigger and heavier the car and engine the more power wasted to move both along.

Sometimes whatever power you have is not enough but that can be a dangerous are on public roads, more often your lugging around an empty trailer of power.

You're also very insulated from the exterior environment and with DSG and all the driver "aids" and "assists" more removed from the driving experience and fun in my view so you need to stimulus of figures. You might or might not go through this phase, we like different things but the higher you take things the sooner you get into ever diminishing returns.

You're with a VW favoured oil and type which if 350 is standard for your model is fine and certainly there's enough about oil beliefs and debates on the site to not need to start another here. The Octavia is a popular model so you can get loads of info in the model/year forum here which I expect you already have.

BTW the coolant (needle gauge at least, I've no idea about the digital and "virtual" ones) is biased to sit rock steady at 90 so as not to worry average driver/owners, I learnt in 199 when for the first time I had a Japanese car, I thought (well didn't really think, well not enough) it was just down to the superior Japanese engineering until I was told different. I was used to cars with mechanical gauges where the needles moved (with varying accuracy) with the real physics and you learnt your car and gauges, in my last one at least if the coolant gauge needle was on 'N' for normal it wasn't it was getting warmer.

If you installed a PS, HP gauge you might see some interesting figures when you're doing normal driving and possibly think back to your Fox even more fondly. 😄

The desulphation phase on a Ctek MXS 5, which may get to a maximum of 15.7V, in my experience never lasts more than a minute or two. The documentation says 8 hour max but my guess is, this is the point the charger asks itself why is it bothering when the battery is clearly toast. You may also see 15.8V if you have selected the reconditioning option, but you're really in the last chance saloon at this point.

The pulse technology used in the desulphation phase is very tightly controlled in respect of pulse width, frequency, rise time, and amplitude of current and voltage. It's nothing like hooking up a 15.7V supply on a thick cable and connecting it to Sizewell B.

Edited 12 August, 202512 Aug by inspectorman
punctuation

4 hours ago, nta16 said:

I'm not knocking you or anyone else, you can have whatever car you like as far as I'm concerned (personally if I only had a choice now of Fox (even £200 fixed) or VRS Octavia I'd go with Fox 9.5 times out of 10, some long boring motorway or dual-carriageway journeys comfort and a bit of entertainment is best). The only VW that has ever interested me was a Golf GTi Mk1 particularly when they were new, near the size of your Fox I'd guess than any Golf from Mk2 on. Plus I'm a shortarse so don't need as much room, but very short legs and long body so do need more headroom than in the back of many coupes or old (70s-90s) Jag saloons.

Don't get too carried away for figures particular PS, HP or BHP, and more so on the speedo. Most often you have far too much more than is needed often only a very small fraction might be used. With heavy German lumps of cars yes you might need a bit more to haul it along and now with modern cars so heavy and with oversized wheels and tyres for fashion sake. The bigger and heavier the car and engine the more power wasted to move both along.

Sometimes whatever power you have is not enough but that can be a dangerous are on public roads, more often your lugging around an empty trailer of power.

You're also very insulated from the exterior environment and with DSG and all the driver "aids" and "assists" more removed from the driving experience and fun in my view so you need to stimulus of figures. You might or might not go through this phase, we like different things but the higher you take things the sooner you get into ever diminishing returns.

You're with a VW favoured oil and type which if 350 is standard for your model is fine and certainly there's enough about oil beliefs and debates on the site to not need to start another here. The Octavia is a popular model so you can get loads of info in the model/year forum here which I expect you already have.

BTW the coolant (needle gauge at least, I've no idea about the digital and "virtual" ones) is biased to sit rock steady at 90 so as not to worry average driver/owners, I learnt in 199 when for the first time I had a Japanese car, I thought (well didn't really think, well not enough) it was just down to the superior Japanese engineering until I was told different. I was used to cars with mechanical gauges where the needles moved (with varying accuracy) with the real physics and you learnt your car and gauges, in my last one at least if the coolant gauge needle was on 'N' for normal it wasn't it was getting warmer.

If you installed a PS, HP gauge you might see some interesting figures when you're doing normal driving and possibly think back to your Fox even more fondly. 😄

I share your physical proportions, although I'm 6 1" - the Octavia is the first car that has seats that 'fit' me properly! My dad's 118i, nice though the seats are, simply don't fit me - the bolsters are too tight, and too low.

I would suspect a Mk1 GTI is actually smaller/lighter than the Fox - just look at how big a current Polo is, compared to a Mk4/5 Golf. In my view though, nothing can make up for weight with regard to handling on modern cars. The new M5 is an absolute monster, but even with ceramic brakes that can stop the Solar System and the best suspension BMW M has to offer, that 2.4 tons can't be hidden. I've been in one, and while 720bhp is... adequate... it feels like a driving a container ship.

I agree too with the DSG, etc - doing 100mph in a 3.0 A6 is like doing 50mph in a Mk1 Golf. Newer cars build up speed so easily, with such little input from the driver.

Mine is 245ps stock, however until fairly recently it was up near the 345bhp mark. When I got the insurance renewal, I decided to take it back to stock(ish), as I didn't fancy paying an extra 150% (yep!) just to have power I wouldn't use. At some point it'll return to a more sensible 310-320bhp, but for now 240ish is enough.

Correct with the coolant gauge - I can't remember the parameters but it's something like 80-120 degrees, and it still reads 90. Only once it gets above 120 or whatever, does it then rise. #VAG

I started a thread about oil yesterday. Bottom line is, stick with what the manufacturer recommends, unless your car is seeing extreme use or is heavily tuned. As an aside, I spoke to several tuning places (one of which runs a 1400bhp Audi R8) and even they said to just stick with (in my case) 0W-20.

Actually - mine has a digi dash, and in RS mode you can see the power being used in kW. It's not very helpful (as I can't multiply the power figure by 1.34 when driving), but the gauge progression gives you an idea of what you're using.

21 minutes ago, inspectorman said:

The documentation says 8 hour max but my guess is, this is the point the charger asks itself why is it bothering when the battery is clearly toast.

It has estimated time to charge an empty battery (what's that?) 60Ah to 80% charged of 12 hours - it gives up at stage 2(?) after 8 hours (minus whatever at stage 1) running at 5A when it thinks something is too badly wrong, which it might be

The battery might be buggered (or dare I suggest helped along to this by the Ctek, whoops, looks like I dare) or if given different treatment revived, or not, for more useful life.

I've had a couple of failures but I've revived a few long "dead" batteries to have very useful more life on an old diesel van too that wasn't getting much use at all. It just takes time and patience something that many don't have in stock particularly professionals which can be understandable. Obviously I didn't use a Ctek charger. 😁

@OccyVRS the Germans marques have always like to over-complicate to show how clever they (think) they are (Simply (not) Clever for VWŠkoda) and VW joined in with the lardy and big vehicles out of the 1970s.

Weight obviously reduces power to weight but as you've put other effects too.

Put the kw gauge on when you're just cruising at 50 mph on a flat road you should have plenty of time to times the figure by one and a third.

Pity VW weren't clever enough to have some sort of gauge to help with battery state of charge to display.

Bear in mind many (most?) of the cars going to tuners might not see much actual real road use. Stick with whatever oil you like, standard or tuned (though I'd want better oils than the VW minimums especially on a tuned car), tuners can often tend to be, like plumbers and engineers (who will tell you how many times you can reuse a nyloc or bent screw 🙃) conservative, but do timely thorough engine oil and filter changes unlike many rushed garage jobs. Doesn't sound like you're keeping the car too many years so it might not matter anyway.

AS I rambler the original Fox, not that I ever saw many, in fact I only remember the one I saw new outside the VW garage it might have been a git smaller but it wasn't parked against a Mk1 Golf to yell and my memory not the best, I just thought it was a sensible sized town car, glorified shopping trolleys now have 17" wheels! Tut!!

I went out in a Beemer 635 CSi back in the day and appreciated the stereo system in it as a passenger and the (proper to me) Audis in the 70 and 80s were nicely done, for the professional family or older man otherwise the Germans just don't know how to style a car to my taste.

The (proper) Volvos had excellent seats, my wife is quite rightly very fussy about seats which makes sense but how she thought the Fabia seats are comfortable is beyond me.

F1 champion James Hunt (from the time when the drivers drove the cars) used to drive himself, for various reasons, an Austin A35 flat-out around London and elsewhere, 948cc, 30-50hp, 690kg kerb weight, like the one Wallace and Gromit use (though I can't see the baby-brain Hamilton being capable of driving one, no or yes, I don't like roundly-round racing and him in particular, said he'd look after where he used to live then ****ed off abroad ASAP and was fiddling around to avoid paying due tax on an aeroplane, mind he had a nasty disliked dad by accounts).

"Oooh look at that Marc, dual exit exhaust, AMG grille, 19" wheels and drilled brakes - that must be a 450bhp CLA45S"

A200. 160bhp. Ugh.

I reckon I'll have the Octavia for another four/five years, I think. It's just crossed 40k and with the use I give it, it will be just topping 100k and 10 years old. That's about as long as I'd run a car that requires some more expensive parts than the average car - especially with the water pump issues, DSG and everything. Certainly, I'd hope to ditch it just before timing chain time.

I do runs to the North of Scotland several times a year (in one hop), so I do have a practical use for an utterly reliable car capable of doing longer distances.

Mind you, at that point it'll be 2029 or 2030. How many manufacturers will still make mainstream ICE cars? I think the average MQB car be discontinued by then, and the replacements are all electric, or hybrid at the very best. So, maybe I'll keep Occy as a second car ;)

@nta16 all plugged in. It's not the best connection to the positive terminal due to the clamp on it, but I don't have the energy to disconnect the battery - it'll do.