Engine tapping an smoking vrs tfsi

Towed the caravan 200 miles and was fine after 3 days of driving pretty hard. turned the car on to tow home and made a horrible tapping sound. 

Had to leave so pulled round to the caravan and noise went down 90% but still didn't sound right and the exhaust was putting out quite a bit of grey smoke. towed home 200 miles without issue and no smoke when it's hot but I can still hear something not quite right. 

Now it smokes a bit after I first turn it on and it's idled for a couple of minutes. Seems like a bit of smoke comes out of the oil cap when I remove it while running also. 

Any ideas?  Going to do a compression test in the next couple of days when I can get a mate to come and look at the gague while I crank. 

My thoughts were guides and stem seals. 

Engines on 140k serviced every 3-5k 

If its the head is there any way to check its defo not the bottom end? I don't want to get the head machined and fit it with all new gaskets just to find its still doing it lol. 

Cheers