Boring Man Tech Talk-Fiat Engine Management Light - Sorted!!

Discussion in 'Tech/Mech General' started by PP Bear, May 3, 2016.

  1. PP Bear

    PP Bear Funster Life Member

    Joined:
    Apr 5, 2013
    Messages:
    2,082
    Likes Received:
    6,035
    Location:
    UK
    I've been plagued by the engine management light coming on intermittently on my 2006 Fiat 2.8JTD. I had the OBI read at a dealers and no faults showed up.

    Usually on a long hill climb or applying too much revs through the gears. It was driving me nuts as sometimes it pulled like a train on an uphill stretch, only to be passing some slow HGV, when the light would come on and reduce power, or cut out the power altogether and never a hint of warning either. Power would only come back when I changed down a gear. Same on hill climbs through the gears. Dangerous and frustrating.

    I read a lot of posts on the problem and the answers seemed to refer to the number 4 injector connection being too tight, leading to a misfire on that cylinder and that some people had reverted to a new loom to sort their woes. I checked all the injector connectors, freed up the loom so that it had plenty of slack, serviced the plugs, but that didn't do the trick.

    Others would talk of the accelerator pedal sensor, but I ruled that out as it was only under load when it occurred and checked out on test.

    The last option I though of was the turbo and turbo boost. While the turbo spins all the time the engine runs, the boost comes into play at set parameters, like hill climbing under load. With a variable vane turbo, it increases the angle that the turbo vanes operate and increases the airflow into the engine. More air and more fuel means better power, so that's where I went next. Serviced the boost valve, added some lube and the problems gone. The engine pulls like a train once more and cruises up hills like it should. Haven't had a hint of the engine management light since and it would always come on when I headed down to Kent for the weekend.

    It's a pleasure to drive all over again and I'm one relieved bear :)

    Library picture shows the rear of the 2.8JTD engine and turbo :)
    image.jpeg
    And a close up of the turbo boost and control arm :)
    Lubed both the control rod and control arm and now operates freely again. Seems they can stick after a period of no use. Simply running them up doesn't put the boost under load, so I guess in the future if I park up, I still need to do the odd run out and put the engine under load :)
    image.png
    Might just be useful info for someone now or in the future :)
     
    • Informative Informative x 9
    • Useful Useful x 3
    • Like Like x 2
  2. injebreck99

    injebreck99 Funster

    Joined:
    Dec 5, 2011
    Messages:
    1,116
    Likes Received:
    1,163
    Location:
    norfolk
    The boost valve you refer to in your photo is actually the waste gate valve which prevents over boosting of the engine, it dumps excess pressure from the turbocharger, in simplified terms, it is preset by the manufacturer and should not be adjusted, just kept free.
     
  3. StitchesnFluff

    StitchesnFluff Funster

    Joined:
    Oct 18, 2014
    Messages:
    1,206
    Likes Received:
    507
    Location:
    Salisbury
    Well done for solving your problem, must be a totally different drive experience now
     
    • Like Like x 1
  4. PP Bear

    PP Bear Funster Life Member

    Joined:
    Apr 5, 2013
    Messages:
    2,082
    Likes Received:
    6,035
    Location:
    UK
    It really has made a big difference, especially to the trust element as I know I can pull out to overtake on hills without worrying that I'd lose power half way up the hill!! :)
     
    • Like Like x 1
  5. DavidG58

    DavidG58 Funster

    Joined:
    Feb 24, 2013
    Messages:
    6,275
    Likes Received:
    12,105
    Location:
    Bolsover, Derbyshire
    even reading the word turbo makes me squirm again, I know exactly what you are feeling now

    hope both of ours now continue to perform as needed (y)
     
    • Thanks Thanks x 1
  6. Geo

    Geo Trader - Funster

    Joined:
    Jul 29, 2007
    Messages:
    9,507
    Likes Received:
    5,559
    Location:
    Mansfield,Notts
    Have you tried it with the engine back in:D
     
    • Funny Funny x 4
Loading...

Share This Page