White smoke

Good morning,

White smoke is an indication of burning coolant. It can come from a head gasket or an intake manifold gasket.

https://www.2carpros.com/articles/replace-intake-manifold-gasket

You will need to have a leak down test done to determine if a head gasket is the failure.

https://www.2carpros.com/articles/head-gasket-blown-test

What has been checked so far?

Roy

I have done a block test, that was fine, The car is nine year old and the genuine mileage is 13,000. I bought it six months ago, not sure if this problem could have be caused by lack of use?

No, you need to do a leak down test. The block test is not accurate at all. That is when you remove the plugs and add shop air into each cylinder one at a time and watch for coolant movement in the radiator. That is the only accurate check for a failed head gasket.

Roy