According to sources inside MINI familiar with future product features, the US market will finally see an auto start/stop system for both manual and automatic transmissions. The first version of auto start/stop made a European debut in 2007 and since then MINI USA has been interested in adding the feature to US bound cars.

The reason for the delay is two fold; there’s been little incentive since the EPA doesn’t recognize such systems in an overall efficiency index and the bigger concern is that the system isn’t free. Again, according to those same sources it adds over $200 per car, thanks to the beefier starter motor, the added electronics and programming. MINI USA couldn’t absorb that cost and didn’t want to pass it on to the consumer. But as BMW has moved to add the technology to almost it’s entire fleet, that price is rapidly decreasing as volume of the system is increasing. Likewise things are changing in the US that make the technology more relevant to the way the EPA measures efficiency- there is an added benefit to automatic transmissions with the current EPA test procedure. This makes a much stronger argument for bringing the system stateside.

We expect the system to debut with the next generation MINIs – the first (the F56 hatch) set to debut in the fall of 2013 as a 2014 model. After that MINI will roll-out other derivatives (the five door hatch, the convertible, Clubman etc) that will all share the technology. Other MINI models such as the Countryman should see the system added over the lifecycle as well.

The system will work identically to the current set-up, which is the second generation of the system. On the manual the Auto Start/Stop function switches the engine off automatically when the car comes to a stop, such as at intersections and in traffic when the car is placed in neutral. When the clutch is depressed to shift into a gear the engine reignites. The manual setup will also feature a shift point display in the cluster that advises the driver of the most efficiency-enhancing moment to change gear and the proper gear to be selected.

On the automatic, the system engages (ie the engine turns off) when the driver comes to a complete stop while in “D” and pressure is applied to and remains on the brake. To start the car again the driver simply lifts their foot off the brake (as they would normally) and the engine seamlessly engages.

The system protects the engine by not allowing the start/stop function until the car is up to proper operating temperature. Likewise it won’t engage if the ambient temperature is too hot or cold or if the demands of the climate control are not being met. The system is able to be turned off manually, detects stop and go traffic (disengages) and can be overridden by turning the steering wheel or relaxing pressure on the brake pedal.

It seems all a bit backward to US that the EPA hasn’t had the forsight to change it’s system of measuring to include such systems. It’s pretty clear that auto start/stop saves fuel (and potentially a lot of it) in commuting situations. It’s nice to know that MINI will finally be taking the initiative (as BMW has). We have long term experience with the European version of the system and have seen the fuel economy gains.