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Is there Technical difference in pump used in MJD, DDi S and Quadrajet?

Discussion in 'Engine Compartment' started by nbvcrao, Apr 19, 2011.

  1. nbvcrao

    nbvcrao Amatore

    Messages:
    235
    Guntur
    Hi everyone,

    Is there any technical difference between MJD, DDis and Quadrajet?

    Fiat engines are used in Swift, Vista also but branded differently. Tech specs remain the same. But Swift, Vista engines emit smoke when floored but not Fiat. Why?

    Is the configuration different with the pump? Quadrajet, used by Vista, means four does that mean pump is programmed to spray 4 times in a stroke, like wise DDiS is used by Swift where D is the fourth letter in alphabet suggesting again 4 sprays in a stroke.

    How many times does it spray in engines used by Fiat as it says MJD? What kind of technology is used by fiat engines as they do not emit any smoke?
  2. vIjAy_kHaSa

    vIjAy_kHaSa Esperto

    Messages:
    1,353
    Panchkula
    Fiat Multijet injects 5 times per injection cycle and Multijet II injects 8 times (MJD II not available in India)
    Last edited: Apr 19, 2011
  3. nbvcrao

    nbvcrao Amatore

    Messages:
    235
    Guntur
    thanks for the update vijay.

    is the fiat MJD patented for 5 times injection spray? how many times does the injectors function in Vista and Swift any idea?
  4. Cinju

    Cinju Esperto

    Messages:
    1,333
    Trivandrum
    Hi nbvcrao... all MJD's have same injection..there is no difference. But in CRDI it differs.
  5. gurjinder

    gurjinder Staff Member Janitor

    Messages:
    3,989
    Punjab
    There is no relation between the name used for the engine and its injections per cycle. Maruti Suzuki explicitly mentions on its website that there are 5 injections of fuel per cycle in its DDiS engine.

    And there is every reason to believe that TATA's "Quadrajet" too employs 5 injections per cycle.

    FIAT cars , and all diesel cars , under heavy acceleration or when lugging the engine do and will always smoke. Unless you have a Diesel Particulate Filter fitted.

    Multijet is nothing but FIAT's term for its common rail diesel technology. Basically, Multijet IS CRDi ( Common rail direct injection ). The basic working is the same. The only difference in the various Common Rail diesel engines in the world today can be in the number of injections per cycle , the maximum fuel injection pressure etc etc.

    Gurjinder.
  6. Cinju

    Cinju Esperto

    Messages:
    1,333
    Trivandrum
    @Gurjinder..you are absolutely right and well briefed. Multijet IS surely CRDI. But what I mean is the patented technology by FIAT and they call it Multijet.Multijet and CRDi or CDi are diesel technologies which are similar except for the fact that in multijet you have multiple injections of fuel per cycle as compared to a single injection as in case of CRDi/CDi. (Ref:- http://www.carwale.com/Forums/viewthread-17673-p3.html)
    Multijet Technology
    http://www.fptmultijet2.com/eng/up-to-8-injections/up-to-8-injections.php
  7. gurjinder

    gurjinder Staff Member Janitor

    Messages:
    3,989
    Punjab
    Im sorry but i disagree. There is no CRDi system present in the world today which utilises only a single injection per cycle as u have suggested. That used to happen in older injection systems which are obsolete today.

    Volkswagen group's TDI engines , Hyundai's CRDi, Toyota's D4D, Mitsubishi's DID etc etc all utilise multiple injections. Thats the beauty of the modern Common Rail direct injection.

    I'll say it again. The basic functioning is the same. One may or may not be more refined than the other.

    E.g. There is a 2.0 CRDi by Hyundai , and the masterpiece 2.0 TDI by the Volkswagen Group, found among others in the BMW 320d.
    Same capacity , same technology, but differences in execution and refinement.

    Gurjinder.
  8. Cinju

    Cinju Esperto

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    1,333
    Trivandrum
  9. gurjinder

    gurjinder Staff Member Janitor

    Messages:
    3,989
    Punjab
    There are both.

    The earlier Skoda Laura came with the PD TDI engine.
    The latest generation Laura comes with a CR TDI engine. Same engine is shared with the Jetta.

    All the Audi's diesel are Common Rail now. The PD tech gave way to the Common Rail tech.

    Aplogies for the error. A Volkswagen Group's engine cannot be found in the BMW. The 2.0 engine is BMW's own. Named the N47.

    Gurjinder.
  10. nbvcrao

    nbvcrao Amatore

    Messages:
    235
    Guntur
    thanks mr. cinju and mr. gurjinder for sharing your knowledge. i felt multijet uses 5 sprays for a stroke which was solely patented by fiat.
    @gurjinder, thanks for updating and sharing what technology is used by other car manufacturers.

    @cinju, thanks for the website link. it is quite informative. especially the fptmultijet.
    Last edited by a moderator: Apr 20, 2011

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