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Rough engine performance at low rpm...........

Discussion in 'General Car Stuff or non-Zed Specific Stuff' started by FRANKIE, Aug 30, 2014.

  1. FRANKIE

    FRANKIE Zorg Guru (V)
    American Zeds The M44 Massive

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    This problem if not with my BMW but with my honda. It is a problem that could happen to any car so I thought I'd run it by you guys to see if anyone had experienced the same problem with one of their cars.
    When I start the car and drive it, everything operates well when the engine is cold. After it warms up, there is rough performance at lower rpms. While I can't rule out the rotor, cap, and wires, it just doesn't seem likely. My reasoning for this is that the car operates normally when cold. The rpm only breaks up at the lower end of the rpm range. At higher rpm's, I can really wind out the engine without it breaking up. Also, if I am very careful in EASING the gas petal during acceleration, there is no break-up at lower rpms. Could it be dirty injectors?
     
  2. Aceman

    Aceman Moderator
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    Hey Frankie how are you ?

    Hard to say without seeing it in person but I would hazard a guess at an air leak in the induction system somewhere. My reasoning is that at lower rpm the engine does not require as much air and if there is a split somewhere in an induction hose the ratio of metered air to unmetered air coming in through the split will be greater having a significantly greater effect on the fuel/air ratio than it does at higher rpm.

    So check all the rubber hoses going from the airbox and the smaller vacuum hoses leading of the manifold as I bet one is split or broken off somewhere.
     
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  3. t-tony

    t-tony Zorg Expert (I)
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    If none of the above Frankie, I would try some fuel system cleaner just in case you have a sticky injector.
     
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  4. oldcarman

    oldcarman Zorg Guru (V)
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    In which case Frankie now knows how to deal with a sticky injector after being with Baaabs!!
     
  5. zedonist

    zedonist Guest

    It may have some rice husk stuck in the intake affecting air flow at low rpm?
     
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  6. FRANKIE

    FRANKIE Zorg Guru (V)
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    ?????????????
     
  7. t-tony

    t-tony Zorg Expert (I)
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    Just a P$ss take Frankie, we in the UK "used" to refer to Japanese motors as Riceburners.;)
     
  8. FRANKIE

    FRANKIE Zorg Guru (V)
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    #8 FRANKIE, Aug 31, 2014
    Last edited: Aug 31, 2014
  9. zedonist

    zedonist Guest

    Too sausagey
     
  10. t-tony

    t-tony Zorg Expert (I)
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    IF I still had a garage in Kissimmee instead of a games room Frankie, that is the type of car I would park in it. Looks gorgeous too, a Z really wouldn't be practical only because of the 2 seats. Shirl's car at home is the same configuration apart from being a folding tin top.
     
  11. David Cullen

    David Cullen Zorg Legend
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    what Honda is it Frankie? year etc... did you do a cel check? could be vacuum leak or iacv
     
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  12. FRANKIE

    FRANKIE Zorg Guru (V)
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    Its a '94 Honda Del Sol 1.6 vtec dohc.
     
  13. David Cullen

    David Cullen Zorg Legend
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    very cool man, you know how to do a cel check?


    View: https://www.youtube.com/watch?v=7bpwfiCxw54



    will be similar to any of the obd1 Hondas, find the two pin block under the dash and bridge it, follow the video above and it will tell you if any sensors are gone, its the first step you should do anyway, failing that id say it is a vacuum pipe, let us know how you get on :)
     
  14. Zeti

    Zeti Zorg Guru (III)
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    Hi Frankie,
    My suggestion is that the air sensor MAF should be the problem: dirty or dead! While the engine is cold , the system delivers rich mixture of gasoline , so you feel the engine running smooth; after the mixture come to the normal level is poor in gasoline and you get a bad running at the idle speed. It's just a guess, but it worth to check the MAF......
     
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  15. David Cullen

    David Cullen Zorg Legend
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    either way, if you do the cel check it will tell you whether it is maf, iacv or whatever
     
  16. zedonist

    zedonist Guest

    Might be brown rice, takes longer to cook......
     
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  17. FRANKIE

    FRANKIE Zorg Guru (V)
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    I have done this on several occasions in the past with good results. My check engine light is not on right now. Perhaps I should do it anyway. Thanks, Frankie
     
  18. zedonist

    zedonist Guest

    Might be a dirty injector, try running some Rice Wine through the fuel.........
     
  19. GazHyde

    GazHyde The Gaz Monkey
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    I wish you would be a bit ricer to Frankie with his serious question, err, whoops... nicer... :ymdevil:
     
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  20. zedonist

    zedonist Guest

    I have been, I got all these potential answers direcry off the ronda rivic site!
     
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