Tachometer Red Line Changing

[Bob Chadwick]

I have a 2017 GS. Recently I've noticed that the red line for my tach has been changing on me. Starts low and then as the car warms up it moves to the 6500 mark. It will then drop down for a period of time and then go back to 6500.

I drove for about 15 miles tonight and the car was completely warm when the red line dropped from 6500 to 5500. This was about a block from home so it didn't change back before I parked it.

Any ideas?

 

[Bob Chadwick]

TTT. No ideas? I‘ve done some reading where other people have had the same issue and the suspected culprit was the thermostat.

 

[Hib Halverson]

My '19 has not demonstrated that "quirk," at least...not that I've noticed. Next time I drive it, I'll have to watch close.

 

[Bob Chadwick]

It went away when the weather got warmer.

 

[Bob Chadwick]

I continue to have this issue. Last night I was driving 45 mph using cruise for a 20 mile section of road and the tach redline (it was actually yellow) sat around 5500 rpm almost the entire time. Got on the freeway at 80 and the redline went to 6500 occasionally dropping down and going yellow.

I can’t find a digital readout of coolant temp but if the gauge can be read based on the lines the coolant seems to be just below 180 degrees.

Any ideas?