I just picked up a 5" Autometer Tach for cheap and wanted to put it in my 85 Turbocoupe. I have everything wired up except for the green wire running off the tach, my quetion is what wire should I hook this up to and where is it? I bought this without directions and looked them up on autometer.com but I was just wondering what specific wire i should splice into on my 85TC so that I dont screw anything up. Thanks
Green wire on aftermarket tachs is usually tch signal input, which goes to the negative (switched) side of the coil. Other wires are probably red - 12V key on, black - ground, white or yellow - lighting.
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Jeff Korn
88 Turbo Coupe: Intake and exhaust mods, T3 turbo at 21 psi, forced air intercooler, water injection, bypass valve, Ranger roller cam, subframes, etc., etc.. // 86 Tbird 5.0 (original owner): intake, exhaust, valvetrain mods, 100 HP nitrous, ignition, gears, suspension, etc., etc.... // 91 Escort: Bone stock winter car // 02 Taurus Vulcan(wifes car)
So I should be looking for a green wire with a yellow stripe at the coil, right? When I hooked one to my 88 I spliced into the green/yellow wire coming off the distributor where the spout is, that you unplug to set the timing.
Best to NOT hook up tach input to the SPOUT circuit. SPOUT circuit just sends computed timing signal to TFI to tell it to fire the coil. This circuit should be left alone. Just tie the tach into the COIL negative side, which is NOT the same as the SPOUT circuit. I dont remember off hand what the coil connector color codes are.... Pull connector off coil, turn key on. One connector terminal will read 12 V, other should read low volts (close to zero). Hook tach to the one that is not 12V. Alternatively, run one side of a test light to ground, and probe both coil terminals with car idling. One will have light on constantly, one will have light flicker. Hook tach to coil terminal with flickering test light.
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Jeff Korn
88 Turbo Coupe: Intake and exhaust mods, T3 turbo at 21 psi, forced air intercooler, water injection, bypass valve, Ranger roller cam, subframes, etc., etc.. // 86 Tbird 5.0 (original owner): intake, exhaust, valvetrain mods, 100 HP nitrous, ignition, gears, suspension, etc., etc.... // 91 Escort: Bone stock winter car // 02 Taurus Vulcan(wifes car)
Ok thanks I got it hooked up now. Just got to find a place to mount this damn thing, its too big for the A-pillar and I'm not drilling any holes into my almost crack-free dash. I have it on the steering column now, covering up the stock tach but I think i need to find a new location for the shift light. That thing is bright and might be too much of a distraction at night where it is now. Ill have to wait and see. Thanks for the help.
I mounted mine on the left side of the steering column.Covers the stock tach.