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Direct Fuel Injection (DFI)

911 Targa 4
Porsche 911 Targa 4 - Direct Fuel Injection (DFI)

Direct Fuel Injection (DFI)

DFI delivers fuel directly into the combustion chamber with millisecond precision. The spray and cone angles of the multi-hole injectors have been optimized for torque, power output, fuel consumption, emissions and efficient combustion.

With Direct Fuel Injection, the engine management system regulates injection timing individually for each cylinder as well as the injection rate for each cylinder bank. This improves the combustion process and fuel economy.

For faster heating of the catalytic converters after a cold start and optimum torque in the upper load range, up to three injection pulses take place per combustion cycle.

DFI improves the internal cooling of the combustion chamber by having the mixture prepared directly in the cylinder. This allows for a higher compression ratio, which helps to deliver more output at the same time as enhanced engine efficiency. Injection is regulated by the electronic engine management system and emissions are monitored by the Lambda sensors.