I once lost a key for an old Skoda Fabia estate had to buy a new one about 3 weeks after I got the new key the old one turned up it would open the car but not start it. I think in your circumstances I would push for new door locks that can only be opened with the coded keys Joe

When I worked for a car rental company a load of keys went 'missing' which led to cars being stolen.

I strongly advise you get the key recoded this week.

that's difficult, i've made quite a nuisance of myself with the dealership. if it is taken i think there's only going to be one suspect. it is insured of course.

When you code new keys to the immobiliser then you have to tell VCDS how many keys to pair. You don't just add a new one on. Also you have to have all keys there with you.

So basically you set between 1 and 4 keys to pair with the immobiliser. You then put each key in the ignition at a time and turn the key, the immobiliser light flashes in the dash to confirm that key has been learnt. You repeat for the number of keys you selected to be learnt, that 1 to 4 figure at the beginning. Finally you get a double flash on the dashboard immobiliser led to say all done.

Then just those keys work. So if 2 keys are paired and you have those 2 keys, then only those 2 keys would start the car. Any other key that worked earlier but was not re-paired at that time would then no longer work.

The only way round this is if a dodgy dealer was doing this who still wants to keep a key for themselves is they would have to pair 3 keys and give you 2. You can ask the car via VCDS, how many keys are door opening matched. That number should be the number you actually have. Hence you can ask that independently. Immobiliser matching requires the pin code which VW no longer give out or in fact even know (only the computers do) , it used to be in a plastic key fob.

The whole process is match 1 to 4 keys in one go. A dealer can't order you a new key and just give it to you, it must be match with any current keys you already have otherwise your current keys would no longer start the car.

15 hours ago, JoePeddos said:

It would open the car but not start it.

I hope my post above explains why. You can recode all your keys if you have the pin code. Or a VAG garage could do it for you without the pin. You can immobiliser learn brand new keys or keys that were historically paired to your car. The one you found must of been historically paired.