This technology has been around for quite some time. It's been tested exstensively. I have yet to hear one report stating it causes wear, but I had the same thought you did when it first debuted.

 

i also thought the same way, until i learned that there's little wear when the engine is warmed up.

as long as there is an override switch, I wouldn't mind this tech.
these are bandaid gimmicks at best.

spend your R&D money on true powertrain advancement. make a fuel sipping engine, and combine old school turbos for more powah

 

Start-stop systems have been making their way in Europe for many years now. In America, they will also start appearing (and Ford plans that ALL of its new Cars sold in the Americas and globally WILL have start-stop system by 2012)

You can believe that more and these systems will grow in number in the years to come.

That said though, even with their growing numbers in regular cars (apart from being commonplace in hybrids), the technology has already existed before.

http://en.wikipedia.org/wiki/Start-stop_system

According to the wiki, they've existed as early as the 1980s in some Volkswagen group subcompacts like the Polo and the old Golf. Apparently, they were rejected back then for being unrefined and expensive.

Who would've thought though that these kind of tech would come back 20-30 years later (mostly primarily driven by stricter fuel economy and emission regulations worldwide)

 

As far as I am aware, this is only true when the engine hasn't reached its optimal operating temperature: basically when the engine is cold. I was once told by a mechanic that every cold start costs the engine an average of 500 km (312 miles) of engine life. Therefore, using this logic, this is apparently the reason why taxi engines have a reputation for reliability - they're in constant use and never have the chance to cool down - literally.

I'm not sure what the deal is on Porsche cars with this feature, but I know that in BMWs equipped with this system, the Start-Stop feature will only shut down the engine once it has properly warmed up.

 

as i said before, start-stop works on average on less than 30% of stops :-).

i bet it works 100% during EU mileage test cycle

 

Porsche is on a desperate mission to raise it's CAFE anyway it can. (CorporateAverageFleetEconomy)

 

Idle-stop is a very simple method -- in concept if not in actual execution -- to increase efficiency and reduce fuel consumption. Western Europe is very concerned about greenhouse gas emissions from vehicles; CO2 emissions are directly related to fuel consumption -- the lower the fuel consumption, the lower the CO2 emitted (that is why we see the grams of carbon dioxide (CO2) per kilometre measurement for every car sold in Europe). The Western European fuel consumption test cycle may be designed to take advantage of idle-stop; the EPA test cycle is not designed to do so, likely because of few and/or very short stops in the test cycle. That is one reason we do not see many idle-stop systems offered here yet. Toyota already offers it on Japanese models but will not offer it here until there is demand for it.

The commonly accepted figure is that it is more efficient to stop and re-start an internal combustion engine (ICE) if the engine will be idling for 10 SECONDS or more. I have also seen a figure that an ICE loses 17% of efficiency due to standby and idling (of course that figure will vary depending upon circumstances including traffic conditions). It understandable why this is a major area of research and development for vehicle manufacturers. If an auto manufacturer can increase fuel efficiency by 15% or more simply by shutting off the engine at stoplights, why not do it?

But there are execution problems. North Americans are too lazy to manually stop and re-start at stoplights: turn off the ignition when stopped and then as the lights approach green again, shift into Neutral or Park and re-start the ignition. But constant stopping and re-starting the engine puts a lot of stress on the starter motor; and constant shifting puts stress on the gearshift linkages. It will have to be automated.

Note that it is already being implemented in a very simple (and almost invisible) fashion now on the newest engines; it is on my 2010 Corolla with the 2ZR engine. It is shutting off the fuel to the engine while coasting: let off the throttle while coasting (downhill, while there is enough momentum to keep the engine spinning), the fuel to the engine shuts off and the instantaneous fuel consumption read-out reads 0.0 litres/100 km.

 

on my panamera it worked pretty much 100% of the time at stops.

 

My wife's FIAT 500C has this feature and it works on 100% of stops once the car is warmed up - usually within a couple of miles. It took a bit of getting used to but now, as soon as you come to a halt and put the gears in neutral the engine stops and a warning light comes on in the speedo. As soon as you dip the clutch the engine re-starts and you're away. A battery condition monitor automatically re-starts the engine if the charge drops below a certain level - like if you have headlights, heated rear window and air-con on full in the morning. The starter motor is a special low noise version, beefed up for this application - that said it'll be interesting to see what reliability is like 4 or 5 years down the line.

 

I was wondering if thats good for the motor too. My gf's Altima Hybrid does that, the motor turns off and on all the time, especially in the city. But apparently, the motor is built to handle it, and you just have to use 0W20 Synthetic (Nissan is very **** about using only this). We saw an 07 for sale with 150,000 miles on it and it was running in perfect condition, mint with only regular maintenence so i guess the engines will last even turning off and on again.

 

well exactly... it works but params have to be met... does Fiat stop the engine when AC is on?