[pfsantos]

Lol on the video...

But yes, between 80 and 100 deg C (the next line without numbers) I wouldn't worry too much. Even if it goes somewhat near the red mark for a little bit (i.e. on a hot summer day in traffic with the A/C blasting) you're ok. But if it goes higher something's wrong.

Having said that, if you're driving gently on a cool day and it's always near 100 I'd wonder about the thermostat not opening enough. Normal driving I always have the gauge between 82-87 ish.

edit: start with the easy stuff...I'd just flush and fill the coolant to the proper mixture (usually 50-70% antifreeze/coolant to water mix) - use distilled water only for the mix...and then see if the temp. changes. Maybe someone's been adding water or just pure af/coolant, and I didn't check your year/mileage and don't know how old your coolant is.