It's the last thing you'd think about in the summer, but the industry can thank German supplier Robert Bosch for the technology that changed the way people start their vehicles.
On a wintry morning, you no longer have to pump your accelerator or pull a choke knob to get fuel to the engine.
Bosch eliminated that need in 1967 when it introduced what would become the first successful mass-produced electronic fuel injection system for gasoline engines. It first appeared on the 1967 Volkswagen 1600.
The technology replaced mechanical fuel injection systems. These pumped a steady stream of gasoline into the engine, which mixed with the air and fired the spark plugs. These systems wasted fuel and energy.
Bosch's first electronic fuel injection system, called Jetronic, was based in part on technology developed by Bendix Corp. It used an early computer and sensors to measure airflow and air temperature. Based on those measurements, it adjusted the amount of fuel delivered. For example, denser air needs less fuel.
So the newer system enabled the engine to develop more power, improve fuel economy and produce lower emissions.
Jetronic gained a reputation for reliability. By the mid-1980s, virtually every European carmaker had Bosch's electronic fuel injection system or its parts in nearly all their vehicles.
But there was room for improvement. In 1979, Bosch introduced the next generation of Jetronic, called Motronic. It tied the ignition and gasoline injection into one central control unit.
In 1995, Bosch introduced electronic throttle control, which it called e-gas. E-gas better controlled airflow and allowed the throttle system to send signals to the fuel, air and ignition systems.
E-gas was the first real drive-by-wire system, says Bob Rivard, vice president of marketing and advanced technologies for Bosch's North American unit, Robert Bosch Corp.
Then in 2000, Bosch introduced its first gasoline direct injection system, on the Volkswagen Lupo.
While other fuel injection systems put fuel near each cylinder's intake port -- called port fuel injection -- gasoline direct injection systems place gasoline directly into each cylinder.
But gasoline direct injection, or GDI, has been slow to take off.
"GDI by its nature is more expensive; it has a more sophisticated calibration process," Rivard says. "And the first system did not deliver on the promised fuel economy."
Gasoline direct injection also can increase emissions, such as nitrogen oxides, commonly known as NOx, and hydrocarbons.
But the evolution will continue -- from Bosch and competitors, including Siemens VDO Automotive, Delphi Corp. and Denso Corp.
Bosch, which is a bigger player in diesel than in gasoline globally, expects to produce a common controller for diesel and gasoline injection systems within a few years. Visteon Corp. and Motorola Inc. supply electronic controllers as well.
Rivard predicts that the industry will atomize gasoline more efficiently. "One of the continuing advancements is to make the droplet size smaller. Instead of injecting through one big hole the size of a pencil head, do four or five small holes to better control the pressure, flow, speed of response," he says.
"It's something we do in diesel today. Instead of one injection per cylinder stroke, in diesel we do multiple injections -- very small, fast pulses."
– Richard Truett contributed