Tachometer lag/issues?

cpark92808

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Chris
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Has anyone noticing that the RPM on the tach drops before it actually does in the engine?
I.E. when accelerating and the gear upshifts, the tach shows drop in RPM prior to the engine actually upshifting.

I am also experiencing tachymeter going up and down randomly when the petrol engine is not engaged.
The dealership is telling me that this is normal.
Anyone else noticing this as well?
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greensprit

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Yes. In EV mode I will sometimes notice the tach go from 0 to 2000 to 0 for a split second while the gear shift occurs. Doesn’t happen all the time, I’d say only 5% of the shifts will cause this. Can’t figure out why.
 

Sboden

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I honestly don't pay much attention to the tach with automatics.
 

michail

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Yes. In EV mode I will sometimes notice the tach go from 0 to 2000 to 0 for a split second while the gear shift occurs. Doesn’t happen all the time, I’d say only 5% of the shifts will cause this. Can’t figure out why.
I have not seen this happen. Could it be the ECU spinning the engine up and then deciding it's not needed?
 

greensprit

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I have not seen this happen. Could it be the ECU spinning the engine up and then deciding it's not needed?
Was thinking the same. I've been trying to see if this happens with higher throttle inputs where engine spinup might be required, but I haven't found any correlation. Weird stuff.
 
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