My advice; drain it and do it again...I nearly made exactly the same mistake with Halfords rubbish, their 'guide book' will tell you it's fine but it's not. You must have 505.01 for the PD engines (2000 - 2006 TDi) I use Eurocarparts always accurate and free delivery. I've used both Triple QX (for PD engines) and the more expensive Castrol Edge, both fully synth, both 5w40.