Interesting reading this:

http://www.thetrutha...t-stop-systems/

So your lovely stop-start system works for about 2 weeks and after that is total utter rubbish. And that is WITH a special stop-start battery!!! So using a manual (with key) stop-start "system" is even worse for a normal battery... Hmmm.

I think it is just awful how companies can make something so unfit for purpose purely to get the efficiency rating on day one and then after that say "who cares, it is not our problem." Awful.

Interesting reading this:

I think it is just awful how companies can make something so unfit for purpose

Only if you actually believe this report of the Pacific Thingy's so-called investigation.

This article has failed to sway my thinking in the slightest.

and, of course, it hails from the USA!

Not sure I believe this. Although not having a Yeti or any other car with Start Stop technology. I would expect that if this was the case that there would be a lot of complaints to manufacturers/dealers. Especially with premature battery failure, or even the lack of start stop feature.

This just doesn't seem to be the case.

I'd like to see a few further reports from other sources before I believe this article. Personally, if it reduced my tax cost from a company car it will be worth it even if it doesn't give the benefits as advertised.

Not sure I believe this. Although not having a Yeti or any other car with Start Stop technology. I would expect that if this was the case that there would be a lot of complaints to manufacturers/dealers. Especially with premature battery failure, or even the lack of start stop feature.

This just doesn't seem to be the case.

I'd like to see a few further reports from other sources before I believe this article. Personally, if it reduced my tax cost from a company car it will be worth it even if it doesn't give the benefits as advertised.

Mine has it.

6 weeks on and it mostly works as advertised.

Occasionally it doesn't stop/start when i expect it should (after quite a long drive) and other times it continues to stop/start when i rather wish it wouldn't (in heavy traffic).

Only once has it behaved totally "odd ball". That is it stopped, i got out of the car to open a gate and when i came back it had a message telling me i had to restart via the key.

I suppose from a Company Car perspective or even a home user you can go for it get the cheaper tax, better(ish) mileage and then just turn it off anyway.

It only illuminates the button and doesn't nag you on the dashboard so you'd really not notice.

My 2cents anyway.

Pacific Crest (and to a degree the US) are touting capacitor technology as an alternative to batteries for start-stop, because they are quite good this technology (the US is so far behind on battery technology).

Many of the emerging battery technologies lose some of their storage capabilities in the early weeks, but they don't continue to do so.

That's why start-stop batteries continue to work for years.

Many of the emerging battery technologies lose some of their storage capabilities in the early weeks, but they don't continue to do so.

That's why start-stop batteries continue to work for years.

That is good then! So this article is just hogwash by a company with a vested interest. Hmmm.

But it does open a wider issue: creating a vehicle that does well in a SPECIFIC test for a Government rating. Be it NCAP or average MPG or a CO2 rating. They are all fiddling it so it works for that ONE test but in a real life crash and/or after continuous use of a DPF or a stop-start system the figures are (seemingly) wildly different.

I have never known a battery on a po van fail (or be replaced yet) other than due to draining due to dodgy electrics, and they must get stopped and started around 100+ times a day over maybe 20 miles traveled.

Lies, damned lies, and statistics

On the same basis, I grew 5 feet in the the first 16 years, so now I must be over 15 feet tall.

I wonder how they'd explain my Fabia Greenline II still going strong after 6 months and 8000 miles, yet the stop-start works every day allowing me to average 70 mpg+

Surely it should have exploded already?

I have never known a battery on a po van fail (or be replaced yet) other than due to draining due to dodgy electrics, and they must get stopped and started around 100+ times a day over maybe 20 miles traveled.

You must be joking! Around here they are just left running.

You must be joking! Around here they are just left running.

That being the case they should be sacked on the spot!

The start/stop is still working fine on my BMW. Nearly 4 years old with the original battery and quite a lot of city driving.

The point is not if the stop/start system as a whole still works or not. The point is that the system works very well on day one to ACHIEVE A CERTAIN CO2 RATING and after that it diminishes. The fact that the car still does its stop/start thing is all fine and well but that does not mean it is doing it as efficiently as it had on day one. Which I think was partly the point of the article posted - baised or not.

The exhaust gases coming out the back of a brand new car is totally different to those coming from a 100,000 mile example. So will you all also say "well there is still fumes coming out the back so yes, it must still be working PERFECTLY"?! Eh? Where is the logic in that!

The exhaust gases coming out the back of a brand new car is totally different to those coming from a 100,000 mile example. So will you all also say "well there is still fumes coming out the back so yes, it must still be working PERFECTLY"?! Eh? Where is the logic in that!

The same logic that says you can buy a new car, with it's VED set for ever based on it's new figure.

Then modify it and make the CO2 much worse a day later.

I guess at the end of the day it's got to be representative compared to other vehicles. Which generally it is... kinda.

Occasionally it doesn't stop/start when i expect it should (after quite a long drive) and other times it continues to stop/start when i rather wish it wouldn't (in heavy traffic).

Only once has it behaved totally "odd ball". That is it stopped, i got out of the car to open a gate and when i came back it had a message telling me i had to restart via the key.

Top one if the engine is hot is will stay on, in heavy traffic I often turn it off.

Second one, if you let it stop on stop/start and then undo the seat belt it has to be restarted manually.

Reading the article I fail to see what they mean by half the fuel efficency unless they mean it accepts less breaking charge. It makes sense to me as what is the point of sitting still with the engine running.

The point is not if the stop/start system as a whole still works or not. The point is that the system works very well on day one to ACHIEVE A CERTAIN CO2 RATING and after that it diminishes.

Well okay, maybe, but I am also acheiving significantly better mpg now than when the car was new.

From limited and I admit unscientific testing I can say I get better mpg with the start/stop switched on than when I disable it, so to me it works.

Whether it is good for the engine and whether it will still work in 5 more years I can't answer!

Hardly surprising that a company that invests heavily in clean technologies might find competitor technologies less than favourable in its "research". Or perhaps they own a company that is developing Generation II power sources?

There was some American research a few years back that compared a five year old gas-guzzling SUV with a Prius and concluded beyond reasonable doubt that the SUV was significantly better for the environment, so I'm always a little bit suspicious of these!

There doesn't seem to be a clear correlation between the charge holding ability of the battery and the resulting MPG - and none of the stop-start vehicles I've used over the past two years have ever had the stereo or wipers fail when stopped.

There was some American research a few years back that compared a five year old gas-guzzling SUV with a Prius and concluded beyond reasonable doubt that the SUV was significantly better for the environment, so I'm always a little bit suspicious of these!

That's because by far the worst thing anyone can do is order a new car. The polution from manufacture is larger than what comes out of an exhaust ppe for a very, very long time.

Buy a second hand car and you have saved a new one being built. More local polution, but less globally.

There doesn't seem to be a clear correlation between the charge holding ability of the battery and the resulting MPG

Indeed, this:

...AGM batteries losing half of the charge acceptance within two weeks after first use (i.e., it loses half of its fuel-efficiency gains)

is the most glaring non-sequitor in the article. Stop-start on its own is not about recovering energy from the battery, it's purely about not burning fuel when stationary. The use if "i.e." suggests that there is a clear link between the first statement and the second but none is ever established that I can see. I can understand how it would affect the efficiency of regenerative systems but the article headline is all about stop-start - they seem to sneak regenerative systems in by a side door hoping no-one will notice and then carry on as if that's the whole of the story.

I've never come across The Truth About Cars before but managing to concoct such a poorly-written and misleading article from a report produced by such an obviously partial source does not give me much confidence in any other supposed "truths" they might offer. (Actually, any web site that purports to tell the "truth" about something is usually best treated with a high degree of skepticism in my experience - unless it's a deliberate and ironic joke.)

AGM batteries are very commonly used as the "domestic" batteries in narrow boats and caravans, and they don't seem to suddenly loose power after 2 weeks.

Ignoring the hogwash from the original article I quoted at the top there is an interesing article in this week's Auto Express magazine where they test the same cars with and without the Stop Start. Nearly all give better consumption with the system on apart from the Golf Bluemotion!!!!! OK it was also better, but where most were better to the tune of at least 5 mpg or more the Golf was only better by 0.1 mpg!!! Hmmm Wonder why.