I am deaf, which I have fit a mechanical rev counter which subtle for old diesel 4 or 6 cylinders to my Citroën AX 1.5D 1995, so I can see when to change the gear, or otherwise without it, I will rev too much because I can't hear the engine. I was used my Tachometer multimeter switch on 4 cylinders, the black connect clip to the negative battery and the positive clip to my alternator where I have fit the wiring looms to the rev counter from the alternator position 'W'.
It all works, but it needs to setting the right rev number by my multimeter, I hold the pedal at 2,000 rpm and adjust the rev counter to 2,000rpm, and it matches the same speed what my multimeter shows, but when I have tried to rev to the red line I was expecting the needle hand stop at 5,450rpm what it says on my Hayne manual, but it halts at 4,200 rpm on the counter. My multimeter numbers have disappeared after 2200rpm, it comes out like this ----
Now I am confused if my mechanical pump have been flick rev limit by previous owner or the rev counter is not working? Because my multimeter it won't show the numbers over 2,200rpm, is there anything I have done wrong with the multimeter?