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O2 sensor upgrade

Discussion in 'The Garage' started by opfor2, Sep 9, 2006.

  1. opfor2

    opfor2 1/2 ton status

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    I would like to upgrade my one wire non heated O2 sensor to a newer heated three wire O2 sensor. Any suggestions on what type of sensor to use and what to do about the connectors?

    Thanks

    Dan..
     
  2. dyeager535

    dyeager535 1 ton status Premium Member

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    GM part number: 25312179; AFS-74 heated oxygen sensor, recommended with headers and the OBD-1 GM setups.

    Cheap out on the O2 sensor, you may get one out of the box that won't work.
    http://coloradok5.com/forums/showthread.php?t=169665&highlight=heated+o2+sensor

    I'd look at "investing" in being able to at least keep it as it comes, with a weatherpack connector. You can get the other end you'll need (probably even from a wrecking yard) you'll just have to get the connector pins/seals to connect the wires on the truck side.
     
  3. opfor2

    opfor2 1/2 ton status

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    I want to do it correctly by using the proper weatherpack connector. Do you know if the connector with a short wire lead is available from GM or maybe NAPA ??

    Dan..
     
  4. Slapperbar

    Slapperbar Retired Navy NDT Examiner Premium Member

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    Summit racing has a kit to make all kinds of weatherpac connectors along with the pin removal and crimper tools.
     
  5. opfor2

    opfor2 1/2 ton status

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    Update:

    The NAPA O2 sensor connector #ECHEC162 does not fit the AFS-74 O2 sensor connector..

    I found the answer to my own question. NAPA Oxygen sensor connector NAPA PN ECHEC162 $ 22.99 This fits the three wire O2 sensor AFS-74. I'm looking forward on completing this mod. Hopefully it will make my truck run better. I installed a set of Edelbrock headers and I'm thinking that the one wire O2 sensor just doesn't get hot enough to make the truck go into "closed loop" fast enough..
     
    Last edited: Oct 22, 2006
  6. Hobbs

    Hobbs Registered Member

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    I have to ask....What is the "closed loop"?

    I just put on a pair of Doug Th. headers on my 88 454 sub. My idiot light has been on coding 44 "lean". I wounder if it is related.

    I put a new 1 wire o2 sensor in to try and solve the problem. Funny, light comes on at a different time. Now it comes on almost exactly 15 minutes of highway speed. Right about the time engine heat gets to 200.

    Hobbs
     
  7. opfor2

    opfor2 1/2 ton status

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    Closed loop is when the ECM is using the data from the O2 sensor to regulate the air/fuel mixture. One problem with using headers is that the exhaust gas does not make the o2 sensor hot enough so the ECM stays in open loop and the air / fuel mixture is not regulated. One way to fix that problem is by upgrading the O2 sensor from a single wire unheated to a three wire heated sensor. A simple fix.


     
  8. Cricket

    Cricket 3/4 ton status

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    You can get a bare weatherpack: NAPA BEL 725177-376 and the pins for 5.00 if you don't mind making your own.
     
  9. randy88k5

    randy88k5 1/2 ton status

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    Yes it is. I bought one. Gm part number 12126012. Looks to be the same ones used for TPS and other 3 wired OEM stuff. Comes with about a foot of lead wire.
     
  10. opfor2

    opfor2 1/2 ton status

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    Are you sure that that's the correct AC Delco part number? When I searched for it on ACDELCO.com it came up as an invalid part number. Maybe this part number is a GM only number??

    Thanks

    Dan..
     
  11. randy88k5

    randy88k5 1/2 ton status

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    That is the GM part number, cant find the package which had the ACDelco number on it.
     

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