Unwanted double signal from VR sensor...

[Jayem]

Im getting double signal from the VR sensor but the signal isnt constant. Double signal occurs in whole rev range. For example idle is around 900rpm and it is shown in computer screen 900 but it goes every now and then to 1800 for few seconds. This is always double, i.e. 6000->12000. Other wise my mjlj is working correctly. I have tryed different clearances between sensor and the trigger wheel, to run the engine without alternator, different edis module and the VR sensor is brand new. +12 and ground is all good. No breakthrough yet.

Now my battle plan is:

1. To make new VR sensor bracket. Sensor is pointing now off by few millimeters from centre of the trigger wheel.
2. To get interference protected wires for VR sensor wiring.
3. To machine new trigger wheel with different tooth profile.


Any other ideas???

[brentp]

Did you monitor the raw VR signal with an oscilliscope? What EDIS module version (4,6,8) do you have?

Are you suspecting that your sensor bracket is vibrating?

Brent

[Jayem]

I haven't got oscilloscope yet. Edis module is 4. Bracket is pretty robust IMHO, but I could weld some extra support to it. My main concern is that the sensor isnt exactly direct to the centre of the trigger wheel(few millimeters lateral). Im going to fix that tonight. Is the sensor vulnerable to bracket vibration?

[dermot]

Screen the VR sensor wires, Ford did, and ground the module end.
Make sure the grounding paths are correct.
Trigger wheel profile should be similar to a Ford one I hope...

[Jayem]

...or so it looks like. I fixed the sensor bracket and replaced the sensor wires with quality microphone wire. I haven't got any dual signals afterwards. I guess the wires were probable problem causer...