Greetings fellows, I've recently come into Audi ownership for the purpose of an economical daily. I've got a PF Audi A4 1.9 TDi 110 (not sure if all the horses are there,) and I've got a Mk2 Golf GTi for fun (although I'm not insured on it right now so it's my dad's daily while his Beetle is in the bodyshop!) Got a few niggles to sort on the A4 and want to make it less tatty looking. I need to clean the turbo vanes using the popular Mr. Muscle trick (although I'll be using an EGR cleaner) and want to know a bit about the EGR blank, I've been under the understanding you need to reduce it in VCDS before you can blank it to prevent error codes, is this correct or can I just ditch it?