2G RPM gauge acting weird

[TortugaEclipse]

This happened randomly as it was and hasn’t been giving me trouble but my rpm gauge will only go up when throttle is pressed but it doesn’t read anything before that. The ecu is reading the rpm so it’s just the gauge. The car is also running decent. It’s hard to explain but this video should explain better.

You must be logged in to view this image or video.

 

[steve]

ECU gets its information from the CAS or CAS and Crank sensors. The tach gets it's signal from the output on the Power Transistor.

 

[TortugaEclipse]

ECU gets its information from the CAS or CAS and Crank sensors. The tach gets its signal from the output on the Power Transistor.

I know it’s been a while but cas and cranks sensor were for sure fine. I swapped the ptu and it was still the same issue. I’m not sure if it is a bad wire somewhere from the ptu to the gauge or if the gauge is bad itself. For the time being I will continue to drive by sound

 

[steve]

I wasn't suggesting that the crank or cam sensors were questionable, just the opposite since the ECU was reporting correctly the issue had to be with the tachometer gauge and how it works. Since you swapped the PTU it would seem like you have narrowed it down to wiring or the gauge cluster.