OK I spoke with the workshop manager at the garage yesterday, my injectors were removed this week and they noticed straight away that every injector had a fair amount of carbon build up. The car only has 21K on the clock, what would this point to - poor additives in a particular brand of petrol used by the previous owner?
Anyway the injectors were sent off to a local company earlier this week where they were tested. The companies test equipment would not test passed 5 or 6 BAR but they believe there is a problem with all of the injectors from testing. The injectors were returned to VW and they have now sent the injectors off to another company (sent Thursday) and they expect to get the test results verbally tomorrow. I've had the supplying (Alfa Romeo) dealer acting on my behalf while I've been out of the country this week but wasn't able to speak with them yesterday, so I'm not sure under who's instruction they decided that the injectors needed to be sent to two different companies. From what I understand it's due to the first companies limited test equipment, or at least this is what the workshop manager confirmed to me. Someone has obviously questioned the test results so this may possibly be the warranty company but I will confirm all of this tomorrow.
It is looking like my car needs 4 new injectors as VW first suggested (which my warranty company declined) - the supplying dealership has said they can get the warranty company to pay but what they need from VW is for them to confirm that fitting four new injectors WILL fix my problem, of course they wouldn't confirm whether it would or not.
Anyway what would cause all the carbon to build upon the injectors on so few miles?