"I believe my cylinder head is suffering from the well known Porous / Cracked cylinder head. I was losing coolant after 5 min drive unless I fully heated up the engine first and even when I had I’d still lose coolant if I sat in the Rev range for the turbo to kick in. If I pulled over the coolant reservoir would be nearly empty or completely empty then I’d open the cap and it would suddenly fill up due to back pressure. I suffered this for 3 weeks stopping 5-6 times on the way to work. The part I needed was going to cost £840 if I fitted it myself or Vw wanted £2400 so I was saving for the part when I came across steel seal. I seriously had my doubts about the product as I have used similar in the past wich have clogged up the coolant system resulting in more issues. But after a bit of reading on how it works I decide to give steel seal a go. It’s now only 4 days later but I have not lost any coolant yet and my car has more power than it has had since I owned it for the last 7 months. I will be keeping an eye on the coolant levels daily still and also changing the cylinder head when I have the funds but steel seal has definitely brought me more time to save if it for some reason does fail."