Tachometer is off.....

[xirforever]

Hi, recently my tac has been way off on my LS400. It says i idle at 100 rpm and below... and so i redline at like 5,400 rpm... Anyway its really bothering me and im just wondering if anyone here has delt with this before? Is there anyway to like recalibrate it? Is that even possible?

Thanks in advance,
Nick

 

[Celsiorous]

The tach in my old Celsior started doing what you describe but would not drop the rev, so if i revved out to say 4500rpm and then took my foot off the tach would keep reading 4500rpm for a few seconds then drop down to an accurate reading.
After a while the tach got worse and worse untill it would not read anything untill the car was quite warm. I had transmission problems and the auto mechanics removed the cluster and sent it to be repaired, it cost $320NZD from memory.