Sorry to jump in on this thread but just a quick question - had my PCV CHANGED AT VW Nuneaton last week and they topped up with a litre of oil - invoice said they used "Helix HX7 10W-40"?
Is this the wrong oil then?
I hope you didn't pay to have your PCV changed? It's very simple to do at home
I don't think the Helix oil meets the requirements of 504 etc. They should have used Castrol Edge 5w30
To put your mind at rest, that oil won't do any harm (oil is oil after all - and it was only a litre).
Just to note: if they got a litre in, your oil was on the minimum level
- check your oil regularly as it won't do your engine any good to be low on oil