Had a problem when installing efi when tacho was connected it would stop it giving spark wile driving, anyone had this problem or know how i could fix it.
im assuming you mean rev tacho? if so then it is wiring wrong. best option is to either get wiring diagram and check it, or get auto electrician to check for you.
me personally i would get the wiring diagram and just re run it seperately. basically dont use the stock plug and re-wire it
The Tacho REV tacho was running of the old points dizzy but when insalling the new elec dizzy there was no mouting point on the distributor, so i mounted it on the negative of the coil,
look into what earlyrolla said but i personally would reqire the tacho and just cut the old wiring/plug used if you cant get it working right.
but i do this on the basis that i am going to get the whole car rewired properly when completely finished so not only is it right but also looks nice and neat.
also running off the coil may short the tacho cause it is supplying over 20k volts, thats why it goes on the dizzy as the condensor prevents shorting. but thats with points im no real expert with electronic dizzy.
if i saw it i would figure it out but off the top of my head not definate.