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  1. #1

    Default 91 Ignition Timing

    Hey all,

    My 91 Suburban 1500 (with the 350) has been having issues when I put a load on the engine since I bought it a couple months ago. I put new plugs, wires, cap and rotor on it right after I got it. I found the coil was bad, replaced it and that helped some. I finally got around to checking the timing today and it was about 8 degrees advanced (supposed to be zero according to the sticker, and yes, I disconnected the timing connector). I adjusted it to zero, reconnected the connecter, disconnected the battery for about 20 minutes to reset everything, and now when I start it I get an SES light with a code 42. I was really happy when I found the timing that far off because I thought that might be at least part of my problem, but now this. Any ideas? Thanks for any input, and happy new year to everyone!!
    - 91 Suburban 1500 2wd 5.7L (mine)
    - 05 Dodge Ram 1500 Hemi (wifes)

  2. #2


    Gah, nevermind!! After I posted this I went to re-check everything and found there is another open single wire connector right next to the timing connector and I had it connected to the wrong one. Connected it to the right one and everything is good. Didn't fix the original problem of it running horrible under a load but at least it's driveable again and now I know the timing is right. I wonder though, why would the timing be that far off to begin with? Would there be some reason somebody would set it like that?
    - 91 Suburban 1500 2wd 5.7L (mine)
    - 05 Dodge Ram 1500 Hemi (wifes)

  3. #3


    timing chain could be worn out.......

    Airforce Veteran (7 years)

    NRA Life Member

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