Sticking tach?

ANyone ever experience a sticking tach prob?

Lately mine has been freezing up at around 2000-3000RPM and not going any higher. It will drop if the RPM's come down, but will not go higher than whatever magical number it chooses.

The needed doesn't stick because if i shut my car and run the gauge diagnostic setup, the needles sweep to 7000RPM no problem.

It seems to only happen if it's hot. It has only happened 3 times in the span of 2 weeks.

Hold in the trip reset button in with the car off. Still holding the button, turn the key to on.

WHen the letters TEST come up in the odometer, let go of the trip reset button.

After a second, the words gauge will appear and all the needles will sweep to their max positions and then sweep back down to 0.

If you start the car and keep hitting trip reset, you can get a digital tach and speedometer.

I think the overlays may have something to do with it. My needle only gets stuck when the interior is scorching hot on sunny days. Maybe the face expands and gets in the way. But i run the above test and it sweeps fine. I dunno.