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hey all just wondering what this box is for its located on the drivers side near where the rear shocks bolt in. noticed it when i removed the rear seat and parcel shelf to install my speakers. i noticed nothing was plugged into it but theres a plug there with the fitting to match it. not sure if its supposed to be plugged in or not.

pics of the box can be seen here: http://s123.photobucket.com/albums/o291/matt_au/

thanks

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https://www.sau.com.au/forums/topic/156697-can-someone-tell-me-what-this-is/
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what could happen if it isnt plugged in?

Nothing noticable. The modulator operates in parallel with a resistor block downstream of the fuel pump. When the engine is cold the ECU activates the modulator which allows a greater current draw through the fuel pump and hence increase pump performance. Once warm it switches off directing all current through the resistor block only.

In laymans terms it allows greater fuel pump performance when the engine is cold (engine usually requires more fuel).

Incidentally, if you were to disconnect the resistor block (silver rectangular block with 2 wires located in the jack compartment in the boot of the R33s) you will find the engine will stall within about 30s after starting a cold engine as the fuel pump will only run when the modulator is activated.

Hope that explains things.

Cheers

Edited by BH_SLO32
  • 2 weeks later...

its always nice to see girls who are not scared of mixing it up with the boys!

I had always wondered what i 'thingy' was.. I really like the way u put that! I'm keen to see more of your in-depth opinions on such things and thingies!

Good work! :D

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