[TestDrive]

Originally Posted by Sideblinder

I need the information specific to the spiffie kit though. They use a telephone jack soldered to the pcb, into which goes a phone line. The phone line then plugs into an ordinary telephone wall jack box hidden under-dash, whose inner connectors each have one of the two signals, or pwr/gnd. I don't know which signal the four inner connectors want and I'm scared I'll explode something if I do the old trial and error

Found the info in google cache page.

Use a flat-head screwdriver to open the box up by prying under the back lip. Now we'll connect some wires.

*
Connect +12V to the green terminal.
*
Connect Ground to the yellow terminal.
*
Connect VSS to the black terminal.
*
Connect the injector signal to the red terminal.

Close the box back up and run the RJ11 cable from the box to your MPGuino. When you plug both ends in, your MPGuino should turn on.