Frequency valve on k-jet cars, is just a fuel injector? | FerrariChat
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Frequency valve on k-jet cars, is just a fuel injector?

Discussion in '308/328' started by stevel48, Oct 22, 2014.

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  1. stevel48

    stevel48 Formula 3

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    #1 stevel48, Oct 22, 2014
    Last edited: Oct 22, 2014
    I know they are NLA now but in my PN (BOSCH 0 280 150 300) searches I often see bosch fuel injectors listed. BOSCH 0 280 150 being the fuel injector and the 300 denoting the fuel volume injected at cubic centimeter per minute. Could a modern electronic fuel injector be used as a replacement for a frequency valve?
     
  2. Crowndog

    Crowndog F1 Veteran

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    #2 Crowndog, Oct 22, 2014
    Don't see how as there is no electronics in the injector to effect valve like behavior. Just a spring and ball.
     
  3. stevel48

    stevel48 Formula 3

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    #3 stevel48, Oct 22, 2014
    Last edited by a moderator: Sep 7, 2017
    not sure either because I have no idea what the inside of a FV looks like. I imagine it's some kind of valve that is open or closed letting fuel pass. When I think of a modern fuel injector it's on or off at X time based upon a signal.
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  4. Rifledriver

    Rifledriver Three Time F1 World Champ

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    #4 Rifledriver, Oct 22, 2014
    Do you need a frequency valve?
     
  5. Rifledriver

    Rifledriver Three Time F1 World Champ

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    #5 Rifledriver, Oct 22, 2014
    For CIS yes, what about all the other versions of fuel injection?
     
  6. stevel48

    stevel48 Formula 3

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    #6 stevel48, Oct 22, 2014
    No no, but in reading about all of the bosch CIS stuff with what I have been doing Brian, I came across a lot of FV threads and what you have written about them. I discovered in my travels that they are NLA but may be repaired. That got me interested in its design and how it works to control lower chamber pressure via fuel regulation. I was thinking that I may be similar to a modern electronic fuel injector.

    I like to stock up on NLA parts when I can for the future.
     
  7. Rifledriver

    Rifledriver Three Time F1 World Champ

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    #7 Rifledriver, Oct 22, 2014
    In in 30 something years I have never replaced one. I have a 328, a TR and a Lamborghini 002. I have a big box of parts I have collected for their future needs. There are almost zero mechanical parts in the box.

    Trim, emblems, things like that become hard or impossible to replace or repair. Mechanical parts almost never.
     
  8. stevel48

    stevel48 Formula 3

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    #8 stevel48, Oct 22, 2014
    Well that's positive news then. I'll take it.
     
  9. Crowndog

    Crowndog F1 Veteran

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    #9 Crowndog, Oct 22, 2014

    Perhaps I misunderstood the question.
     
  10. stevel48

    stevel48 Formula 3

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    #10 stevel48, Oct 22, 2014
    Still, I wonder if it came down to it could it work. The FV looks like a modern injector but I have no idea if it functions like one.
     
  11. stevel48

    stevel48 Formula 3

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    #11 stevel48, Oct 22, 2014
    I know more now. Seems to be controlled by a duty cycle like the FV.

    How does a fuel injector work?
    A fuel injector is nothing more than a high-speed valve for gasoline. Fuel injectors are normally fed power whenever the ignition key is on. The computer controls the negative, or ground side, of the circuit. When the computer provides the injector with a ground, the circuit is completed and current is allowed to flow through the injector.
    An injector in an engine turns on and off very quickly to control the amount of fuel delivered. The amount of time an injector is turned on and delivering fuel is known as the duty cycle.
     
  12. Rifledriver

    Rifledriver Three Time F1 World Champ

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    #12 Rifledriver, Oct 22, 2014
    This applies to electronic injectors only.

    No, it is injector duration and is usually measured in MS.

    A FV is measured in duty cycle because it is constantly turning on and off very rapidly. If during a 5 second period (5000 ms) it is open for 100 25ms periods (2500 ms total) that would be a 50% duty cycle, 50 periods would be 25% and 150 periods would be 75%. I just picked the 25 ms figure for illustration purposes. In reality I have no idea how long the open time is on a FV. I am sure it is shorter.

    Mechanically they are the same but the job is different and their operation is measured differently.

    Because that degree of control could be exercised in electronic injectors a FV was not needed in electronic systems.
     
  13. Crockettsonny84

    Crockettsonny84 Rookie

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    #13 Crockettsonny84, Oct 23, 2014
    Last edited: Oct 23, 2014
    Basically all the frequency valve is: an electrically driven orifice that regulates fuel going back to the tank. This is solely dependent on the mixture sensed at the cats. If it's too rich it'll open more; too lean? Open less. Etc etc.. The likelyhood of this part failing is virtually nil. It's the lambda sensor controller that usually goes bad and there IS a test for them. I'd look into that first

    It is not an injector by any means


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