My astra mk4 1.6 8v has been playing up recently. I was sitting inside the car with it running after 40 mins of driving and noticed the car was heating up to 100c which i started worrying thinking it was going to be headgasket failure as it is a common fault on these models. But if im driving the car does not over heat and it cools down and heats up like it normally would. I done a test to see if the expansion tank bubbles up and nothing but noticed the fan would not cut in. So i have replaced the temp sensor on the inlet manifold and still no luck.
Could it be the fan is faulty? or something else?
Thanks in advance