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LS2 constant limp mode…

This topic contains 4 replies, has 3 voices, and was last updated by  GM Fan 1 year, 2 months ago.

  • Author
    Posts
  • #773265

    Pauldw501
    Participant

    Hi and new to the forum.

    I’m down under with a Holden HSV R8 fitted with a LS2 engine, Since I got the car I’ve had her go into limp mode and throw throttle body related codes. P1516 and P201 but also see P2135 here and there.

    I’ve swapped pedal twice and throttle body 3 times to no evail.

    Once upon a time she’d only do this when I flogged her, another time when RPMs were high, but now it just does it totally randomly, for example earlier today when cruising down the highway at 110kph and boom!!… ‘check engine’ light on dash and limp mode activated.

    It’s got so bad I need to drive with OBD2 scanner connected and ‘clear codes’ one press of a button away.

    PLEASE PLEASE… it’s your engine so I’m praying someone can give me something to try to stop this happening.

    Any advice most appreciated…

  • #773274

    Pauldw501
    Participant

    Wow lol

  • #773290

    Parts Man1
    Participant

    P201 indicates a voltage problem between the pedal and the throttle body but P2135 indicates a problem in the fuel injector harness and man, I hate to try and find that…Good Luck..

  • #773293

    Pauldw501
    Participant

    Yeah been a total nightmare…

  • #773346

    GM Fan
    Participant

    Ive got a lot of experience diagnosing and data logging the ls platforms (currently own lm7, ls2, and 2 lt1’s). If i were you id start by checking the voltage at the alternator (i have seen them throw weird harness codes like this). If that checks out then check all connections going to the TB (take apart the connector and check pins and then check all grounds. If it happens randomly then that sounds like a loose ground/connection. Keep us posted

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