Changed one of my air pressure gauges and air (Hadley) horn relay. No more air leaks. Now my problem is the tachometer is not working. 1. When I start motor tach sweeps from 0 to max and stays there or it goes to 0 and stays there.
2. Have taken wires off and put them back on in same position.
3. Sometimes when key is on and motor started, if gauge is indicating 0 the needle seems to tick a little.
Clean the connections. Clean ground
Swap wires around , in that order.
Connections clean and tried swapping wires around...2 white wires and 1 green.
Tach uses a simple pickup visibly located on top of bell housing between engine & tranny. Make sure wires are clean and attached. Sensor wires are known to sometimes fall off.
Gauge startup movement is just the gauge booting up with ignition power. Has no bearing on sensor connectivity.
Sensor sends pulses and an adjustable setting in the tach calibrates pulses to RPM.
Re Crimp the wire ends. A definite maybe
Did u ever fix ur tach?