Evening lads.

I think ive asked this before but im still having troubles and have some more info.

My Smiths motorsport tacho doesnt work. Ive had it running for the last year but it seems to switch off for a second when im over 7000rpm, it happens randomly and at different revs. Its revieving the signal straight from the ZX12 ecu which is also feeding another smalled digital tacho which works fine.

Tonight i took the back off the dash to see if the wiring is ok and it is, but i noticed the tacho input was for a coil ignition (last engine was old and on carbs), looking on the net shows that this is the problem, the tacho cant keep up with the signal input type as ive got it on the wrong wire. So ive changed the input to the correct wire for efi signals but when i do this i get no reading what so ever.

Not sure what to do now other than buying a replacement at £200+

Any tips?

its this one:
http://www.caigauge.com/page11.html

[Edited on 23/3/11 by Moorron]

Have a look at driving directly of the coil pack using 3 diodes, wiring diagram on the Megajolt site.

its a good idea but i hate running extra wiring that should really work with the one in the car. I could test the tacho on another car, with a efi signal to see if the tacho will read it. If it doesnt then i know the tacho efi input is broke and it will need repairing or replacing.

If it work then im stuffed lol

cheers anyway