Grounding 1UZ ECU casing in a fibreglass car

Discussion in 'General Discussion' started by Mat Grant, Apr 3, 2018.

  1. Mat Grant

    Mat Grant Member

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    Hi all,

    I've fitted a 1UZ to a Lotus, it is running, but the ECU is not bolted in yet, just sitting on the floor of the passenger footwell. I was planning on mounting it at the end of the passenger footwell, using rubber shockmount fittings, and install a cut down version of the plastic cover from the Soarer the engine was taken from. The car is made of fibreglass, so my question is, does the ECU casing need to be separately grounded? If so would tapping into one of the ECU grounds be adequate, or should I run a ground wire to a ground point on the chassis/pedal box? Or does it have a built in ground for the casing? (makes mental note to test this in the car)

    Any advice or suggestions welcome... For info my ECU is the 1992 Soarer three plug 40:40:40 type.

    Thanks, Mat

    P.S. sorry if this is in the wrong section.
     
  2. cribbj

    cribbj "Supra" Moderator Staff Member

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    In general, it's bad practice to mix instrument (ECU & low level inputs) grounds with power grounds and other noisy sources (injection, ignition, etc.). So my kneejerk recommendation would be to try and run a separate ground for the ECU and its inputs.
     
  3. Zuffen

    Zuffen Super Moderator Staff Member

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    My ECU is in a Fibreglass body and it isn't grounded and never has been.
     
  4. melvinmelvin

    melvinmelvin Member

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    mine likewise, not grp but acryl plastic box, no separate grounding
     
  5. Mat Grant

    Mat Grant Member

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    Thanks guys, that's one less thing to worry about.

    Cheers, Mat.
     

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