GM Truck Club
THE PREMIER CHEVY TRUCK & SUV FORUM
Founded in 2004 ~ We're the #1 Chevy Truck & SUV Forum.
Silverado & Sierra | Tahoe & Yukon | Suburban & Yukon XL | SUV & CROSSOVER

P0440...

Discussion in 'GM Powertrain' started by jcerny, Sep 30, 2009.

  1. jcerny

    jcerny New Member

    Joined:
    Jan 31, 2009
    Messages:
    26
    Likes Received:
    0
    Well, got my first 'check engine' light with my 2002 'burban LT 4WD. P0440, 'evaporative emissions control system malfunction'. Anyone have any experience with this code on similar trucks?
    #1
  2. jcerny

    jcerny New Member

    Joined:
    Jan 31, 2009
    Messages:
    26
    Likes Received:
    0
    SO... I did a search after posting... Found these possible causes:

    1) Defective fuel cap
    2) EVAP canister or host cracked
    3) Purge of vent solenoid defective
    4) Vacuum leak at engine.

    Any one have anything to add?
    #2
  3. ippielb

    ippielb New Member

    Joined:
    Feb 6, 2009
    Messages:
    1,549
    Likes Received:
    2
    I had this in my 2002 silverado, on top of your gas tank there is a black valve, it is plugged full of dust(in my case) all you need to do is if it's mildly clogged, is take your air compressor and blow out the valve(first take it off and disconnect the line to your charcoal box, make sure they're both disconnected and blow out the line, both ways, to get all the dust out of the line.

    Here's a little diagram.

    [​IMG]
    #3
  4. jcerny

    jcerny New Member

    Joined:
    Jan 31, 2009
    Messages:
    26
    Likes Received:
    0
    Charcoal box #4? Valve #2?
    #4
  5. jcerny

    jcerny New Member

    Joined:
    Jan 31, 2009
    Messages:
    26
    Likes Received:
    0
    Stunned and amazed... a new gas cap fixed it.
    #5
  6. jcerny

    jcerny New Member

    Joined:
    Jan 31, 2009
    Messages:
    26
    Likes Received:
    0
    Ok... New gas cap didn't fix it for long. Suppose I'll check out that valve and hose. I suppose the hose is a dealer only part, what about the valve?
    #6

Share This Page