I bought a tach (iEquus) from Kragen. I have a big block with a Summit distributor with a tach port.

I have never had a problem wiring a tach before. Done quite a few. This one is giving me fits. I can not get it to operate. Red wire to power source (when key on), black to grnd., white to light source and green to tach port. Set up the electronic tach per instruction and the darn thing will not work. Took it back thinking it was bad. Got another one. Doesnt work either. Tried wiring direct under hood. No matter what I do, will not work. Any clues. Is there a better tach I should use? This is a daily driver, no drag strip action. Help before I go nuts. Thanks mw

Just my opinion but buy an Autometer... I wish I would have, makes life easier if you plan to add a msd box, ect. I thought I would get by just fine, by not purchasing an Autometer and learned my lesson.....

Goodluck i hope you get it sorted out...

maybe green doesnt mean dist. on that tach... could it be white? It should have screws to open it. Make sure that the wires going into tach are connected properly. On a mallory I had the wires connected to the spots inside the tach clearly said dist., ground, etc.