01 chevy duramax diesel question

Discussion in '4X4 Truck Talk and Repairs' started by tigger_tat_55, Aug 30, 2007.

  1. tigger_tat_55

    tigger_tat_55 New Member

    Messages:
    301
    State:
    cali
    hi there,

    have what sounds like a vacum leak coming from under the hood at about 2000 - 2900 rpm, seems to happen only when the truck is under load, I cant get it to happen when the truck is stopped. It sounds more like air is being blown out instead of sucked in. I have checked most of the fittings around the turbo. any idea's what this might be?

    got about 105,000. miles on the motor.

    thanks
     
  2. Philiagorillia

    Philiagorillia New Member

    Messages:
    296
    State:
    Missouri
    Are you sure it isnt just a vacuum leak somewhere? Is it effecting performance when you are driving the truck, also what are your gauges saying when you hear this sound?
     

  3. tigger_tat_55

    tigger_tat_55 New Member

    Messages:
    301
    State:
    cali
    so far I have not found a vacum leak. I keep looking, the gauges are normal, no loss of power. truck runs fine other than this issue.
     
  4. Dave L

    Dave L New Member

    Messages:
    1,012
    State:
    Minnesota
    It may be the whining of the super charger that you are hearing. I have an '02 that makes a sound like you describe, been there since day 1 and runs like a top. If you aren't getting any computer messages on the dash and it is running fine, I would forget about it.
     
  5. tigger_tat_55

    tigger_tat_55 New Member

    Messages:
    301
    State:
    cali
    not sure what im going to do. I guess if the noise had always been there, I might be able to ignore it. It just started a bit ago and I wonder why??

    oh well, will prob have to take it to the dealer......I hate to do that!!


    thanks :big_smile:
     
  6. Philiagorillia

    Philiagorillia New Member

    Messages:
    296
    State:
    Missouri
    There are no superchargers on these trucks, they all are turbo diesels. And the spool up of the turbo can make this so called whine you may be hearing as well as the stock wastegate letting off excess boost from the turbo...
     
  7. ShilohRed

    ShilohRed New Member

    Messages:
    4,339
    State:
    West Tn
    Check the clamp on your cross over pipe for the Turbo. If its not tight it will do that also.
    My 04 started it and that was what mine was.
    Pete
     
  8. Rookie12

    Rookie12 New Member

    Messages:
    1,324
    State:
    Kannapolis, NC
    Diesels don't have vacuum, they have boost because they have a turbo and not naturally aspirated. What you are hearing is an intake leak. This would be a vacuum leak on a car, but it's a boost leak on a diesel. Easiest way to find it is with spray bottle and soapy water. spray all hoses, clamps, etc. from turbo to intake. If you got an aftercooler, spray it down as well, the bubbles will tell you where your leak is. It will only do it under boost, so you will not detect it at idle as it will have little boost at this point. Get it taken care of, boost leaks left alone will cause turbo problems and let your exhaust gas temps get above normal which turbos don't like. Turbos aisn't cheap, but fising a boost leak is usually a hose or clamp. They make intake system pressure checkers too, but if you dont' wrenck for a living, I wouldn't buy one. good luck!
     
  9. tigger_tat_55

    tigger_tat_55 New Member

    Messages:
    301
    State:
    cali
    thanks for the help!!! I have been gone for the past 3 weeks so now that i am back I will give it a try..

    again thanks for all the help!!:smile2: