Now - is the time to check and recharge your car battery

[AnnoyingPentium]

2 minutes ago, nta16 said:

But doesn't the car already do that with it's readouts

 

The accuracy of those readouts is highly questioned. Some people were reporting figures like 80mpg on a Fabia vRS when they were seeing 65mpg via "proper" (for lack of a better term) calculations.

[nta16]

Please note - I am not a mechanic or expert in anything.

 

On 30/11/2021 at 12:39, roottoot said:

If a modern car Euro 6 plus can not do 450 miles from 45 litres with people in the car at UK NSL.s then VW Group really should be discontinuing that vehicle.

Would you never encounter traffic jams and have to overtake, wouldn't be much point getting the vRS, unless you mean with a vRS and you'd get even more in a non-vRS driving it like it's a non-vRS.

 

All interesting stuff to someone from the 70s (not in their 70s,yet).

 

Edited 14 September, 2022 by nta16
Please note - I am not a mechanic or expert in anything.

[TerFar]

18 minutes ago, nta16 said:

I am researching it, I'm asking you and others. 😉

 

 

That's my point, it's not brim to brim.  I can fill my old car up to brim, literally to the back of the petrol cap (not a good idea) and I know this takes time and several attempts to let the filling petrol settle, the hose tip can only be at the very start of the filler aperture (do we count the lost vapours from this) again not a good idea.

 

Doing the fill to first click and mileage is fine and reasonably accurate, good enough, but no point going to too many decimal places and a rounded up or down whole figure for mpg is fine is but it not that accurate, more accurate than VW figures no doubt and more real world.

The point was correct. The fuel is cut off by the computer deactivating the injectors during overrun conditions. Even though the engine may still be going through its cycles driven from wheels by the momentum of the vehicle, absolutely no fuel is injected into the cylinders. Obviously, the computer reenables the injectors as the revs fall below a predetermined speed so that the engine / car doesn't stall. Cleverly, once you are stationary, the computer disables the injecters again to stop the engine (start / stop control). 

 

As for brim to brim topping up; over a period of time, this will average out, but accuracy is compounded by the difference in the density of fuel as the mean temperature changes. In the cold Winter, density is higher, in the Summer it is lower. Although the fuel stores at garages are underground where the temperature / density is not subject to a big change, in your car tank, it is more significant. But once again, over a length of time, these difference will balance out. 

 

So the accuracy of your figures will be quite accurate over a couple of years, but over a single holiday or just a random month they'll be no more than a rough guide. 

[TerFar]

36 minutes ago, AnnoyingPentium said:

 

Nope. I just drive the car and add petrol as and when required.

I have month by month spreadsheets running for my home energy usage. I have 10 years gas/electricity/water consumption and almost 7 years of solar generation and (free) hot water heating. I'm a 75 yo geek! 

[johnh510]

1 minute ago, TerFar said:

I have month by month spreadsheets running for my home energy usage. I have 10 years gas/electricity/water consumption and almost 7 years of solar generation and (free) hot water heating. I'm a 75 yo geek! 

 

Must give you a warm glow....

 

I'll get my coat

[TerFar]

19 hours ago, xman said:

 

You misunderstand micro hybrid charging strategy. Switching off stop/start does not mean the battery will get charged over 80% or more.

 

The ~80% SOC is an average target that the battery management will try to maintain over the medium term. The 20% up to 100% is "headroom" to allow energy to be harvested when the engine is on the overrun, slowing the car as a supplement to the brakes. Energy recovery using the alernator as an electrical brake, this is when the SOC is allowed to climb towards 100%

 

Energy recovery is restricted by the charge acceptance of the battery. AGM has higher charge acceptance (quicker/higher current) than EFB, new batteries better than old, temperature dependent.

 

A SOC of 80% or more means sufficient capacity remains for smooth stop/start operation to run auxillary electrical loads during engine stop as well as the engine restart. In practice the target will vary quite a bit, if you have lots of electical demand, headlights, fans, radio,wipers, heated seats perhaps the battery management will maintain a slightly higher level to ensure stop/start is possible, or it may decide to disable stop/start because the electrical load is too high, or SOC is too low or the battery is tired (HOC).

 

Then there is the scenario that you put your foot down and accelerate, the alternator will turn off and allow the battery to take the electrical load, saving a bit of fuel in the anticipation that it can recover it later during an overrun/brake phase. If SOC trends too low or very high electrical loads are present the alternator output will be turned up to compensate.

 

In practice micro hybrid is a complex mix of calcs, voltage/current/temperature/time measurements, estimates, a bit of guesswork and propriety algorithms.

 

In short, switching off Stop/start will not alter the ~80% target, but it will stop the battery cycling to lower SOC by prevent the engine stopping.

 

 

As the car can't anticipate when you will turn off the engine (maybe it could if you navigate using the on board sat nav to a destination, but I doubt it does that) then SOC when the car is parked could be different to the 80% but on average it probably will be close(ish)

Precisely why I disconect the BCM sensor from the negative battery terminal. Once disconnected, the alternator charges like it always did before all these complexities were forced upon us! In this freezing weather, it's good to know the battery is 100% when left out overnight. 

[nta16]

Please note - I am not a mechanic or expert in anything.

 

On 29/11/2021 at 20:13, AGFalco said:

For most of this road the instant fuel consumption reading is ZERO fuel being used.

My apologises to AG Falco, on rereading this bit I now see it clearly has "For most of this road" which I misread as on this road.

 

Edited 14 September, 2022 by nta16
Please note - I am not a mechanic or expert in anything.

[Ootohere]

@nta16

The same trips on the same roads in the same towns and cities year after years will include overtaking, following tractors, bikes etc and various speeds and overtaking.

Scotland does not get that many new motorways, dual carriageways or bypasses built in 50 years.  There are many more average speed cameras or mobile cameras where there are better / quicker roads / routes.

 

A Euro 5 1,390 cc 180 ps DSG Mk2 Fabia vRS could do 10 miles per litre. Even better than that with a bit of easy ozzy driving or no passengers.

Even better remapped so not running the factory Engine Management.

No Stop / Start, no coasting function.

The Twinchargers could be great, but VW never did the production right with too little R&D.

(The CEO of VW North America bogged off to Volvo after introducing the Defeat Device TDI's to the USA & Volvo got the Twinchargers sorted.)

 

VW Group gave the Sister cars as in the VW Polo GTI / Seat Ibiza Cupra from 2013 & the Audi A1 185ps which were heavier and on wider tyres a lowed VED band and better consumption figures.

This is VW Group engineering, as in the more expensive cars must look as better performing by manipulation. 

http://briskoda.net/forums/topic/319834-vrs-mpg-only-please

http://briskoda.net/forums/topic/461848-real-world-mpg-in-your-vrs

 

 

 

 

[nta16]

Please note - I am not a mechanic or expert in anything.

 

Now I didn't know you were referring to Scotland, been a few years since I've been there but it certainly suits faster cars with it's more open, flowing less congested roads not so well suited to my current car, and more suited to steady driving helping mpg.

 

There is certainly "lies, damned lies and VW statistics".  I saw on here were IIRC the Fabia has rear bodyweights.  It's a matter of many records that I think of VW cars being heavy the from at least the Mk2 Golf in my memory and I know from personal experience of lighter cars the difference to power to weight someone like me can make to the car.

 

Years ago when I went out on a passenger ride in a Fabia vRS at Bruntingthorpe 'track' I was very impressed by it, felt more like a 2 litre, I think it wass factory standard.

 

A very quick look at your links and you put - "Real world is 37-42 mpg over the months, years. 45 mpg at UK NSL's is easy to get, so you can get 450 miles from a brimmed tank, some get near 600 miles hypermiling."  Now I follow more what you meant by NSL driving but it would vary over countries and counties and I was thinking 70 not 60, my mistake, silly really as I now drive at 60 on the motorway and so are many others now it seems.

 

In the mid-90s for at least a month I travelled up and down parts of the M1 and M6 at 50mph in a late 60s Spridget (well bits of it were) as I'd had a recon gearbox installed and it vibrated between 50 and 70.  I was often in the inside lane with a quarter to half a mile between me and the next vehicle in front of me and the other two lanes nose to tail often at 55-60.  Often too I would have to slow to prevent me undertaking at 50 mph yet there was still about quarter of a mile of empty lane space.  Used to get good mpg then.

 

Edited 14 September, 2022 by nta16
Please note - I am not a mechanic or expert in anything.

[AnnoyingPentium]

5 minutes ago, nta16 said:

Years ago when I went out on a passenger ride in a Fabia vRS at Bruntingthorpe 'track' I was very impressed by it, felt more like a 2 litre, I think it wass factory standard.

 

Was it a Mk1 vRS or Mk2 vRS? I'm asking because the Mk1 was basically just a handful of CC's short of being a 2 litre.

[nta16]

Please note - I am not a mechanic or expert in anything.

 

Must have been a Mk2 then as the lad said it was a 1.4l IIRC - and that it was a turbo plus supercharger, I've got a drip type memory, but still not always very accurate. 😄

 

ETA: it was green if that helps, IIRC. 😄

 

Edited 14 September, 2022 by nta16
Please note - I am not a mechanic or expert in anything.

[AnnoyingPentium]

Just now, nta16 said:

Must have been a Mk2 then as the lad said it was a 1.4l IIRC - and that it was a turbo plus supercharger, I've got a drip type memory, but still not always very accurate. 😄

 

 

Aye it'll be the twincharged 1.4, 180ish bhp IIRC.

[nta16]

Please note - I am not a mechanic or expert in anything.

 

On 30/11/2021 at 15:41, AnnoyingPentium said:

 

Aye it'll be the twincharged 1.4, 180ish bhp IIRC.

Yes it was quick but the joe public crowd at the charity day were waiting more for the likes of a red Fezza (with a driver that didn't know his car, cooked the front brakes) so being one of the 'Gate' stewards I shouted if no one else was going in the car I would, and I did.

 

Edited 14 September, 2022 by nta16
Please note - I am not a mechanic or expert in anything.

[AGFalco]

11 hours ago, Wino said:

Doesn't everyone have a spreadsheet of these records?

 

I keep the fuel receipts in a diary and work it out the long way.

But I have only done this since June 1985.

Examples below.

 

 

Thanks, AG Falco

[AnnoyingPentium]

4 minutes ago, AGFalco said:

 

I keep the fuel receipts in a diary and work it out the long way.

But I have only done this since June 1985.

Examples below.

 

 

Thanks, AG Falco

 

My Grampa does it in a much smaller diary, one of those little pocket ones.

[nta16]

Please note - I am not a mechanic or expert in anything.

 

On 30/11/2021 at 18:48, AGFalco said:

But I have only done this since June 1985.

I'm not criticising this or you but I will ask what many (including me) are thinking - why?

 

Edited 14 September, 2022 by nta16
Please note - I am not a mechanic or expert in anything.

[nta16]

Please note - I am not a mechanic or expert in anything.

 

ETA: gratuitous photo from (27th November) 1985

(we didn't have a car in June 1985)

 

 

Edited 14 September, 2022 by nta16
Please note - I am not a mechanic or expert in anything.

[Breezy_Pete]

The physicist Lord Kelvin stated: “When you can measure what you are speaking about, and express it in numbers, you know something about it, when you cannot express it in numbers, your knowledge is of a meager and unsatisfactory kind; it may be the beginning of knowledge, but you have scarcely, in your thoughts advanced to the stage of science.”
 

[AnnoyingPentium]

18 minutes ago, nta16 said:

ETA: gratuitous photo from (27th November) 1985

(we didn't have a car in June 1985)

 

 

 

Where was that taken?

[TerFar]

45 minutes ago, AGFalco said:

 

I keep the fuel receipts in a diary and work it out the long way.

But I have only done this since June 1985.

Examples below.

 

 

Thanks, AG Falco

Are we all that geeky! 😉

[TerFar]

37 minutes ago, nta16 said:

I'm not criticising this or you but I will ask what many (including me) are thinking - why?

 

That's an easy question to answer. It is so that when I make my final confession, I am able to repent for the exact amount of poisonous gases I have generated. That is my 'carbon neutral' solution. 🤣

[nta16]

Please note - I am not a mechanic or expert in anything.

 

On 30/11/2021 at 19:08, Wino said:

The physicist Lord Kelvin stated: “When you can measure what you are speaking about, and express it in numbers, you know something about it, when you cannot express it in numbers, your knowledge is of a meager and unsatisfactory kind; it may be the beginning of knowledge, but you have scarcely, in your thoughts advanced to the stage of science.”

Yes and if he was an artist we can guess how he'd do his paintings.

 

Edited 14 September, 2022 by nta16
Please note - I am not a mechanic or expert in anything.

[nta16]

23 minutes ago, AnnoyingPentium said:

 

Where was that taken?

Well, there were three castles in a triangle and it's not Grosmont I think Raglan, definitely Wales.

 

[AGFalco]

33 minutes ago, nta16 said:

I'm not criticising this or you but I will ask what many (including me) are thinking - why?

One of the first car's I had was a 1966 D Reg Mini.

I felt that the 850CC car was using more fuel than it should.

After finding out how to work out the fuel consumption I calculated it to be doing 26MPG.

It was an SU carb problem that was causing this excessive consumption.

 

I now run 3 cars, all do more than 10000 miles per year and all fuel is paid for by me.

 

30000 miles at 26 MPG at £1.449 per litre or about £6.50 per gallon is about £7500 per annum.

30000 miles at 58 MPG at £1.449 per litre or about £6.50 per gallon is about £3350 per annum.

The other two cars in the family do better MPG than the Fabia.

 

The petrol Fabia I have had since new and replaced a Diesel car with 133000 miles.

I was hoping to average 50 MPG in this which would be worse than the previous car.

The first two tanks in the Fabia were 50 and 49 MPG.

By taking an interest in running costs and finding ways to improve this helps me financially.

The journey time and average speed of my regular journey to work and back has not changed in the last five years.

But I have improved fuel consumption by almost 20%.

 

You do the math.

 

Thanks, AG Falco

 

 

[nta16]

Please note - I am not a mechanic or expert in anything.

 

Yes I would do an mpg check on an old car new to me or if I thought a car wasn't running right or to test out new parts or "improvements" but that would be it.  I don't like to keep many virtual records let alone paper records.

 

Unless there's a fault in the car other than changes in some parts, perhaps as service replacement much of the improved mpg I'd have thought would be from driver technique including vehicle preparation.

 

I certainly don't like doing the math (another American invasion) but I can do (very) simple maths and it's took me hours to remember what had a re-emergence in the 70s petrol crisis (such as it actually was here) the 'TelUlog' (I couldn't get the name right), no converting from (UK) gallons then of course.

 

 

(48.3mpg)

Edited 14 September, 2022 by nta16
Please note - I am not a mechanic or expert in anything.