Hi guys I'm running a Haltech e6x with a EL dissy in a EF with a AU motor..lol just wanted to know if I would be able to use the stock EF tacho?? I know pin 7? i think it is pink/blue is the tacho wire but every time I hook up the haltech AUX out wire and use that as a 0 to 12V tacho wire in the haltech or I can use a PWM output#2 but either of these dont work... I even when from the - side of the coil but still nothing... any help of this would be good as its starting to drive me nuts..

Hi,

I don't have the answer, but I hope I can point you in the right direction. In the EF / L the ECU sends a signal to the Tacho of 1 revolution. This means the Tacho is the same for a 6 or 8. If you look in the dizzy, there is a slotted disk. ( in effect, it is more like a cap ) It has a slot for each spark pulse, and there is one longer slot. The ECU sees this to sync the sequential injection pulses, and to know 1 revolution has been made. This then sends a signal to the instrument cluster, which has a lot of smarts in it. Now when you connected the coil pulse to it, you may have damaged it. The signal from the coil has " Back EMF " which means you may have sent a high voltage into a low voltage digital device. Test your cluster first, then if it works see what you can find with Google, you will need a circuit to clamp the voltage from the coil, and divide by 6. I would think that there are commercially made things to do this, and it would only take a handful of parts to make.

Plan B is if the Cluster has been damaged, fit the " guts " of a cheap aftermarket Tacho into it. Not as hard as it sounds, I have done a few. The hardest part normally is making the face, but that is already there. Now when you get one, look for one that has a center spindle. Some have a big hole in the middle of the face which they hide with the Redline marker needle.