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Whats Direct Injection Technique?

  1. Aug 8, 2008 #1
    What is direct injection technique which is being used in automobiles nowadays.
  2. jcsd
  3. Aug 9, 2008 #2
    its a method of injecting fuel into the engines through a nozzle so that the flow of petrol is controlled using chips to increase fuel efficiency...it replaces carburetors of conventional petrol engines...

    note:deisel engines have never used carburetors and are conventionally fuel injected from yore
  4. Aug 9, 2008 #3
    direct injection is squirting fuel right in to the combustion chamber
    most gas car fuel injection squirts in to the intake ports out side the combustion chamber before the air intake valve
    so fuel can pool and must be sucked in with the air intake

    direct injection is more efficient but requires an injector that can stand hi-temps
    and pressures inside the combustion chamber so costs far more to make and the fuel injection must be timed and amount controlled far more requiring greater computer control also adding to costs
    Last edited: Aug 9, 2008
  5. Aug 11, 2008 #4


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    Direct injection also injects the fuel during the combustion stroke rather than during the intake stroke, as in conventional fuel injected engines, eliminating pre-ignition problems that high-compression engines are prone to.
  6. Aug 17, 2008 #5


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    I think Ray's post sums it up best, if you're asking about gasoline (petrol) direct injection. Note that most modern diesels use a direct injection strategy.
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