when my car is running the temptaure will go to 90 dregess but when i drive it will lose all tempture and move up and down but the tempture in the fan is still warm
You need to fit a new thermostat.
It's a fairly easy job, any garage can do it, doesn't have to be Vauxhall dealer.
Make sure they use the same colour of anti-freeze when they top it up.
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