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Blue smoke from exhausts on tick over

Discussion in 'Engine, Drivetrain, Fuel and Exhaust' started by Hughesey, May 17, 2019 at 10:34 PM.

  1. Hughesey

    Hughesey Member

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    Recently whilst caught in a traffic jam I noticed a worrying amount of blue smoke issuing from the exhausts, it doesn't happen not that I've noticed whilst driving at normal road speeds, the car was stationary for approx 30mins but disappeared when returned to normal driving. Leaking injector???
     
  2. Blobcat

    Blobcat Moderator

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    Blue is normally oil and leaking valve stem oil seals used to be the culprit
     
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  3. Dean Fletcher

    Dean Fletcher Senior Member

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  4. OP
    Hughesey

    Hughesey Member

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    Thanks for the replies, would the fact that the car isn't losing any power and is still responsive have a bearing on any remedy?
     
  5. LostKiwi

    LostKiwi Senior Member

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    It's a diesel so unlikely to be valve stem seals. Petrol engines are far more susceptible due to manifold vacuum drawing the oil down.
     
  6. John Laidlaw

    John Laidlaw Senior Member

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    Little too much oil?
    Turbo seals on the way out ( but then you’ll notice a power drop and responsiveness)?
    Edit: forgot to mention quality of the oil itself- changed recently or not?
     
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  7. OP
    Hughesey

    Hughesey Member

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    That's a good point John as the service history is a bit wooly after 2016, having said that, the info in the car says 15500 miles before service E.
     
  8. Ossymechanic

    Ossymechanic Member

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  9. Uncle Benz

    Uncle Benz Senior Member

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    How many miles on it? It might be worth checking the pcv valve on the back of the offside cylinder head for blockage. I have found that OM642 are prone to dripping fuel injectors. The smoke builds up at idle, and it stinks. It has a tinge of blue to it in my experience, possibly because it starts to wash the bores. It will quickly disappear after a few hundred yards of driving. Any decent Indy can pull the injectors and get them tested. Any dripping is immediately obvious under test. I'd certainly do this before considering replacing the turbo or any big tear down work.
     
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  10. OP
    Hughesey

    Hughesey Member

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    Mileage has just turned 99,000
     
  11. Uncle Benz

    Uncle Benz Senior Member

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    I'd be testing the injectors first then I think. My money is on them.
     
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  12. OP
    Hughesey

    Hughesey Member

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    Injectors, that sounds expensive.
     
  13. Uncle Benz

    Uncle Benz Senior Member

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    Testing is cheap. New ones are not, sadly.
     

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