Company touts an actual 3% savings at the pump in real world use.
Wayne Gerdes -
CleanMPG - July 6, 2012
The really sharp looking 2013 Ford Fusion – With the 1.6L EcoBoost, expect a 37 mpgUS highway number. With Auto Start-Stop, maybe a 26 to 27 mpgUS city rating might be in the cards? We’ll know soon enough.
From a release yesterday, Ford is saying it has at least 25 patents pending for the very affordable “
$295 Auto Start-Stop option on the upcoming 2013 Ford Fusion.
According to Ford, the ability to shut down the engine when the car isn’t moving has always been one of the most popular features of hybrid vehicles. In reality, the ability to shut down the engine while moving is far more important as we all know but Ford has to start somewhere. I digress… The new Start-Stop system will be available on the new 2013 Fusion with the 1.6L EcoBoost engine.
Auto Start-Stop switches off the engine when the car stops and instantly restarts it when the driver releases the brake.
The new Fusion is the first Ford vehicle to offer Auto Start-Stop with an Automatic. Since an automatic transmission needs to maintain internal hydraulic pressure even with the engine off, Ford added an
electrically driven pump to the transmission along with the upgraded starter motor and the higher capacity absorbed glass mat (AGM) battery.
In order to minimize launch delays after a restart, the engineers wanted to keep the transmission in gear even with the engine off as opposed to shifting it into neutral.
The Auto Start-Stop control system is always considering the next engine restart and by monitoring the 12V’s current capacity and driver’s accessory load (radio, headlights, climate control…). It will then decide whether or not to allow a shut down with subsequent spin up and restart moments later. If the electrical load is too high, Auto Start-Stop may be disabled to prevent a rough restart or being stuck with a discharged battery and inability to spin up the engine for a restart.
Voltage blending - While the engine is running, the alternator produces about 14 to 15 volts, but the battery only produces 12 volts with a full charge. When the Fusion is slowing down with Auto Start-Stop enabled, the load model tracks the vehicle speed and deceleration and then calculates when to ramp down the voltage from the alternator to the battery-only level before the Fusion stops. This blending helps to ensure the driver doesn’t experience any light dimming or sudden fluctuations in ventilation fan speed.
The Auto Start-Stop team has filed several patent applications related to the signal monitoring and controls for the climate control system. On hot summer days, the sun’s energy can heat up a car interior within minutes, quickly making things uncomfortable for the driver and passengers. The Auto Start-Stop monitors the temperature of the evaporator core that starts to rise before the occupants even feel a change inside the car. When this happens, the engine will restart sooner allowing A/C to kick in prior to a driver/passenger getting uncomfortable.
The 2013 Fusion with Auto Start-Stop helps drivers save on gas without getting in the way.
While Ford is poising Auto Start-Stop as a way to save upwards of $220 per year, the average owner will more than likely receive a benefit 1/5th of that amount. This still provides an excellent payback at the pump over the life of the car but when it comes time to change the battery 5 to 7-years down the road, lager CAP AGM’s are more expensive reducing the incentive somewhat. In addition, speaking with colleagues that have driven the very seamless BMW Start-Stop system, most turn it off soon after the newness wears off due to the continuous noise of a subdued start motor continuously spinning the motor up after each stop.
When Auto Start-Stop systems are standard equipment from all manufacturers, we will enjoy the fuel savings without having to delve into the cost factors most including myself struggle with when evaluating or setting out to purchase a new car… After all, even $295 to turn the key a few times a day seems like a lot compared to a CleanMPG’ers daily routine.