Anyone know what is causing my Tach to do this? I have the video link below.
Thanks
Tach Video (https://www.veed.io/view/b3f3e6d8-0e2e-4b9b-ab4b-f1b409bce7a9?panel=share)
It looks to me like that is the normal start up sequence when the ignition switch is energized, but that there is no tach signal present. That can happen when the dash tach signal wire has become disconnected. Ours does the same thing but there is no delay when you energize the ignition switch. I haven't as yet found the dash tach signal lead which I believe is somewhere on top of the transmission. I would love to fix it, but since I use VMSPC to monitor the systems, it hasn't been a high enough priority to address considering the competing priorities vying for my time.
Thanks Don
Do you think this could be something as simple as a dirty connection? I have checked the sensor on the bellhousing and all the wires are connected and look good. It does this all the time in intervals of every 15-20 seconds.
Have you ohmed out the wire from the sender to the tach. Looks like it is not getting a signal. I don't remember how to check the clearance between the flywheel and the sensor. Something like screw it in with the engine not running until contact and then back it back out maybe one turn. If there is too much clearance it will not work.
I have not tried that yet but I will, thanks Ron
On my 98 u320 there are 2 diagnostic buttons under dash hood that if pushed can cause tach not to work.