I'm interested in the answer to this too. I would like to know what the path of the tach signal is, from the computer all the way to the green signal wire that plugs into the back of the tach.

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1993 W124 300D 2.5L Turbo, OM602.962
2000 Chevrolet Cavalier, 2.4L DOHC
2002 Ford Explorer, 4.0L SOHC
2005 Toyota Prius, 1.5L

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