O2 sensor Question

Discussion in 'Engine Performance + Maintenance' started by Casey Price, Jul 5, 2019.

Sponsored By: Car Parts
  1. PlayingWithTBI

    PlayingWithTBI Desert Old Guy

    Messages:
    803
    Likes Received:
    303
    Joined:
    Jan 3, 2019
    Location:
    Tonopah, AZ
    It's a good start getting the O2 hooked up, now your next issues;

    Code 32 - EGR will come on after the engine is warm and you're cruising over 45MPH, that's when the ECM tells the EGR to open so, it seems your EGR valve (circled in blue) either is stuck/dirty, or your vacuum hoses aren't hooked up right/connected.

    Code 43 - ESC can be a couple things, your ESC (Elictronic Spark Control) module (circled in red) that the knock sensor is wired to isn't getting feed back from the KC (the ECM checks periodically) or the module is bad. Another problem could be your ICM (Ignition Control Module) in the distributor is bad, this was my problem recently.

    This is assuming all of your wires are connected properly including grounds! Both EGR and ESC are in the same wiring harness on the passenger side of the throttle body.

    upload_2019-7-10_13-21-44.png

    When you shut off the engine the CES light will go off but the Malf codes will stay stored until you restart a certain amount of times - usually ~30 - 40 times or disconnect the battery.
     
  2. Casey Price

    Casey Price Newbie

    Messages:
    5
    Likes Received:
    0
    Joined:
    Jul 5, 2019
    Location:
    Hankamer,Texas
    Ok before I left work I check to see where the KS was and it is also new. Unplugged it and plugged it back in. Connection was tight.

    Something I forgot to tell ya was every morning when I leave the house there seems to be a really annoying miss with the motor. I have to baby the throttle to keep it from laying on its face. Hammer on the gas and it doesn't do anything but ease into it and it's not as bad.
     
  3. PlayingWithTBI

    PlayingWithTBI Desert Old Guy

    Messages:
    803
    Likes Received:
    303
    Joined:
    Jan 3, 2019
    Location:
    Tonopah, AZ
    That really doesn't mean much, you need to verify voltages/connectivity.

    Could be related to your code 43, it's really hard to go further in diagnostics without a good scanner to data log parameters when the issues occur.
     
  4. randomguy

    randomguy I'm Awesome

    Messages:
    106
    Likes Received:
    33
    Joined:
    Feb 25, 2018
    Location:
    Oregon
    Knock sensor wire is easily damaged by retards replacing starters. Mine was snapped in three places by the previous owner. I ended up running a new wire.

    Easy way to check it is with a multimeter. If you get infinite resistance between the knock sensor connector and ESC connector then your wire is broken.
     
    DerekTheGreat likes this.
  5. randomguy

    randomguy I'm Awesome

    Messages:
    106
    Likes Received:
    33
    Joined:
    Feb 25, 2018
    Location:
    Oregon
    I would think the code 32 is the reason why it’s running like crap. A stuck EGR is going to continuously pump exhaust into the intake tract. If you used anything but an AC Delco EGR valve there is your problem.
     
  6. PlayingWithTBI

    PlayingWithTBI Desert Old Guy

    Messages:
    803
    Likes Received:
    303
    Joined:
    Jan 3, 2019
    Location:
    Tonopah, AZ
    Could be, another reason data logging would help, you can look at fuel trims now that we have a working O2 sensor.
     
  7. randomguy

    randomguy I'm Awesome

    Messages:
    106
    Likes Received:
    33
    Joined:
    Feb 25, 2018
    Location:
    Oregon

    Agreed though it’s pretty easy to determine if the code 43 is the knock sensor VS a problem with the ESC.


    Does it knock or ping before the light comes on? If so that’s the ECM doing a self check for the knock sensor and if it’s reaching the point you notice it then there is an issue with the knock sensor circuit. I don’t recall the parameters but it’s warm engine above a certain speed. ECM checks the knock sensor by advancing the timing until it detects a knock signal, however if it advances the timing to a certain point without detecting a knock it throws a code and retards timing to the point the truck becomes a slug.
     
  8. Casey Price

    Casey Price Newbie

    Messages:
    5
    Likes Received:
    0
    Joined:
    Jul 5, 2019
    Location:
    Hankamer,Texas
    Yes. I'm like here we go and bam CEL comes on and it turns into a slug.

    I'll check the KS this weekend. probably just run a new wire just for the heck of it.
     
  9. WillieWeed

    WillieWeed Newbie

    Messages:
    10
    Likes Received:
    3
    Joined:
    Jul 5, 2019
    Location:
    tn
    i`m surprised that it runs very well after the initial start up. when mine went bad after the warm up cycle and goes to the normal run cycle it would die or run half [email protected]@ed then die going down the road. it threw all kinds of codes. just my 2 cents
     
  10. randomguy

    randomguy I'm Awesome

    Messages:
    106
    Likes Received:
    33
    Joined:
    Feb 25, 2018
    Location:
    Oregon
    [​IMG] [​IMG]
    [​IMG]

    The above is accurate for my 88.
     
    kennythewelder likes this.

Share This Page