Ford To Offer Fuel-Saving 'Start-Stop' System

Ponca City writes "The Detroit Free Press reports that Ford plans to offer start-stop systems on many cars in 2012 that save fuel by turning an engine off when the vehicle is idling and quickly restart it when the driver releases the brake or steps on the gas pedal, improving fuel economy by 4% to 10%, depending on driving conditions. The system, common in Europe on cars with manual transmissions, is already in use in the US on gasoline-electric hybrids, including the Ford Fusion Hybrid. Automakers have been reluctant to add the feature to cars in the US because the testing method that the Environmental Protection Agency uses to determine fuel efficiency ratings doesn't include many stops and thus doesn't recognize the technology's effectiveness."

Re:Cold weather

[lyml]

Well we've been using it for a while in Sweden and it's pretty cold up here. No problems so far.

Re:Fuel-Saving?

[bobdotorg]

On fuel injected cars you pay the penalty on a cold start - until the engine and exhaust / emissions systems are warmed up, the car runs rich (open loop).

Once the car is warmed up, the ECU (engine control unit) will go into a more efficient closed loop operation, using O2 sensor output to set more efficient fuel levels. Shutting off the engine for a moment will not send the system back to the less efficient open loop.

Re:Why hasn't it been done before?

[Ebbesen]

Well, Volkswagen made the Lupo back in the 90s. It was able to achieve 78 miles to the US gallon with a 1.2L diesel engine.

So, I guess he's full of it, if the battery pack on the big American cars are unable to store enough energy.

Re:Cold weather

[Shuntros]

It behaves perfectly well in cold weather. I have a 2.0L/200bhp diesel BMW in the UK where it's been sub-zero (that's on the rest-of-the-world temperature scale) for the last month. A number of pre-requisites have to be met for the car to commence the start-stop behaviour, such as the engine having warmed up sufficiently, battery charged etc.. There's also a button on the dash to disable it as it can get a little annoying during rush hour due to frequent stopping in heavy traffic. It took a couple of weeks to get used to, but it now feels strange to sit at the lights with the engine running. It's very fast aswell; kills the engine below 5mph when the car is in neutral and clutch is out, then the moment you hit the clutch to pop her back in gear she fires up again, so quickly that it's almost impossible to get your foot on the gas before she's running.

Not sure how they plan to implement it for cars which run in "stupid mode" (automatic transmission); presume it'll crank it when you take your foot off the brake to drive off.

BMW specifically recommend NOT warming the car up for long periods before driving off; it's no longer necessary due to today's technology, nicosil-plated cylinders etc...

Re:Buy a Ford!

[afidel]

Guess you missed the 365HP/350lb ft, 25MPG Taurus SHO with the 3.5 V6 then, eh? Adding this would just improve that fuel economy while costing nothing in performance. Compare it to the 3.7L 305HP/275lb ft Acura TL with the same fuel consumption in a 400lb lighter car. Ford became pretty serious about US fuel economy a couple years ago and they mortgaged the company a couple years ago to achieve it and it's rightfully paying off for them.

Re:Cold weather

[Anonymous Coward]

What about Variable Cylinder Management [wikipedia.org]?
Or Variable Displacement [wikipedia.org]?