Is the car fitted with a duel mass flywheel? If so this should be fitted at the same time as the clutch ideally.
Could it be a slipping timing belt/chain?
The sensors are notorious for failing. The adblue systems have been added by most manufacturers now to reduce the nitrates from the exhaust, not necessarily because of the emissions scandal. Adblue systems have been fitted to lorries for at least 10 years or more.
I'd recommend speaking to an Audi independent specialist to get another quote
Could be the switch but could also be the module. I'd recommend a diagnostic check to see if any fault codes flag up. Also when was the gearbox last serviced?
Well crap, there goes the sump 🤦♂️ on the plus side at least the car is drained of oil for its service which is due In the next 3 weeks. Plus the underside is well oiled, which should prevent rust for the next 10 years 😂
I agree with Gregg, if it's a metallic rattling sound then it could be a heat shield. It could also be a failed exhaust mount causing the exhaust to bang on the underside of the car.
I agree with Gareth, you need to be speaking to the warranty company asap. As Gareth has suggested it could be something as simple as the expansion tank cap not sealing properly.
Welcome to the forum you'll find the members on here are a friendly and helpful bunch 🙂
Lovely looking car 👍 I'd recommend speaking to local auto locksmiths.
Also there are plenty of shows this year where we're having club displays. You'd be more than welcome to display your Audi with us. Have a look under the events section. First show is 16th April. Simply Audi at beaulieu, it's the best show of the season.