It's the last thing you'd think about in the summer, but the industry can thank a German supplier for the technology that changed the way people start their vehicles.
On a wintry morning, you no longer have to pump your gas pedal or pull a choke knob to get fuel to the engine.
Robert Bosch GmbH 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 replaces mechanical fuel injection systems. Mechanical systems 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 a very 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 bulletproof reliability. By the mid-1980s, virtually every European automaker had Bosch's electronic fuel injection system or its parts in nearly all their vehicles.
Most domestic and Asian manufacturers licensed Bosch's technology and produced their own components.
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.
The innovations didn't stop there. In 1995, Bosch introduced electronic throttle control, which it called e-gas. It 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, said
Bob Rivard, vice president of marketing and advanced technologies for Bosch's North American unit, Robert Bosch Corp. in Farmington Hills, Mich.
Then, in 2000, Bosch introduced its first gasoline direct injection system, on the VW Lupo.
While other fuel injection systems inject fuel near each cylinder's intake port -- called port fuel injection -- gasoline direct injection systems inject gas directly into each cylinder.
But gasoline direct injection, or GDI, has been slow to take off, especially in the United States.
"GDI by its nature is more expensive - it has a more sophisticated calibration process," Rivard said. "And the first system did not deliver on the promised fuel economy."
Gasoline direct injection also can increase emissions, such as nitrogen dioxide, commonly known as NOx, and hydrocarbons.
As with all new technology, the price of gasoline direct injection will come down, Rivard said. Suppliers could reduce the precious metals in the catalyst, and better engine performance will remove some of the exhaust cost, he said.
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 gas injection systems within a few years.
Though diesel and gas combustion processes are different, a lot of the software could be commonized, Rivard said.
Visteon Corp. and Motorola Inc. supply electronic controllers as well.
Rivard also 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 said. "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."
Rivard pointed to additional room for improvement:
Staff Reporter Richard Truett contributed to this report