Shift light not working in harmony with tacho woes.

[Gingerbread Man]

Right.

I brought a shift light for my track/ road car. Part of a bulk buy, so I wasn't alone in buying and fitting the shift light.

Everyone else who brought theirs tapped into the wires going to the tacho, earth, live and the signal feed.

Fine I thought and followed suit. I seem to be the only one who has problems when doing this. The RPM signal doesn't seem strong enough to be able to supply the shift light and the tacho. My tacho goes sporadic and doesn't read correctly.

I've checked and double checked the connections and all are fine. Correctly crimped with male, female and piggy back crimps. The shift light detects the signal and lights up, so it's getting all the right boxes ticked.

After a bit of researching my problem, I've read about similar problems and that a signal isolator (?) is the answer. This would hopefully let my shift light and tacho work in harmony.

Now, thinking that it would be easy (and it should have been) to connect up, the talk of signal isolators and the lark is out of my depth.

I've looked into local auto electricians, but with the prices I've seen, one hour of their time is basicly the cost of the shift light(£60). This doesn't make it worth going to a local pro. So I hoped that someone knowledgeable would be able to point me in the right direction, either with the guidance of making a signal isolator for me, helping me to cobble together one or any alternative would be fantastic.

I've drilled a hole in the scuttle for the wire to go through now, so I've got to have something there to serve the hole a purpose, working or not!