Problem - When driving, the temperature gauge sometimes gets to 100 degrees celcius. Is this ok?
Possibility 1 - Normally my temperature gauge doesn't exceed 95 - 100. Check coolant level.
Possibility 2 - Check that the fans are working.
Possibility 3 - 100 degrees is on the high side but isn't in the red.
Possibility 4 - You may have to bleed the system. There are two nuts on the coolant pipes under the panel that covers the exhaust shroud. Turn car on and wait for fans to start. Undo nuts and wait for fluid/coolant to squirt out solid. Then tighten nuts. Do not over tighten as it is aluminium.
Possibility 5 - My car fluctuates between 85 and 95.
Possibility 6 - Check cap on coolant overflow tank. If it is loose, it can cause this problem.
Possibility 7 - When idling on hot days, my gauge reads high (100) but when I start moving, it comes down.
Possibility 8 - Could be a faulty water temperature sensor.
Possibility 9 - Outside temperature can change the running temperature.