Just received my defi tacho today, downloaded the Pdf wiring diagram and plumbed it in. Everything then got setup as to the manual so I started the car and it all worked fine. This was until I revved the car anyway... The tachos response is terrible and very slow in comparison to the standard gauge and my apexi gauge which is quite odd. I have also removed all of the other gauges from the wiring just to see if they were causing the problem but it's still really slow to react I'm gonna nip out again and wire the earth directly to the battery but I'm pretty sure the earth I have used is comple