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O2 Sensor - Bank 1 - Where is it?

Discussion in 'General Chevy & GM Tech Questions' started by F E Knucklebuster, Feb 9, 2010.

  1. F E Knucklebuster

    F E Knucklebuster New Member

    I'm pulling a P0135 code - bad O2 sensor on bank 1 sensor 1.

    Where is the bank 1 O2 sensor located on a gas 2004 6.0 2500HD?

    Common sense tells me to look at it this way - am I right?

    Bank 1 Sensor 1 - Driver's side before convertor (front)
    Bank 1 Sensor 2 - Driver's side after convertor (rear)

    Bank 2 Sensor 1 - Passenger's side before convertor (front)
    Bank 2 Sensor 2 - Passenger's side after convertor (rear)
    Last edited: Feb 9, 2010
  2. MrShorty

    MrShorty Moderator Staff Member 1000 Posts

    I think that's right. Bank 1, by convention is the bank with the #1 cylinder. I haven't looked at it in a year or so, but doesn't GM start numbering cylinders from the driver's front? Quickest answer would be to pull out a manual and look it up (my manual's at home, so I can't look until then).
  3. vncj96

    vncj96 New Member 1000 Posts

    the banks go buy your front cylinder, so cylinder one is bank one,
    sensor one is pre cat and #2 is strictly there to monitor the cat
  4. Z_10002003

    Z_10002003 New Member

    It's just below the driver side manifold in the crossover pipe. super easy! That sensor will cause havoc when it goes bad, I had one fatten up the short term fuel trim so bad, that it blew black smoke out the tail pipe like a cummins.
  5. 06MonteSS

    06MonteSS New Member

    O2 bank 1 sensor 1 is the driver's side, front O2 sensor, the one before the CAT...
  6. F E Knucklebuster

    F E Knucklebuster New Member

    Thanks. Might have been a false alarm. I reset the Check Engine Light and haven't thrown any codes yet. If I need to change any sensors I know where they are now.

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