Long story, please read. I really need your advice. I drove 100 miles yesterday to trade my BMW Z3 for an Audi A6 Avant 2.5 TDI, I arranged the deal over the phone as it was an Audi Dealer and i was advised that they would carryout a 172 point check (I should know better 17th car in 14 years). I gave the car quick exterior visual inspection, didnt look too closely trusting the main dealer aspect. 1st atempt to get home. So i collect the car, I get about 1 mile down the road and notice bluey sometimes grey smoke. There is an amber warning light on, i understand this is the TC light is illuminated. Called that garage and took it back in. The tech looks at the car and after 20 minutes says too much oil has been put in but this would burn off, I asked about harm to the cat, turbo etc and was told not to worry. 2nd atempt to get home. Got approximately 12 miles into my journey to hear an extremely loud chattering noise under the car, I pull in to the services at Gretna and take a look at the car. i notice a few things: 1. No splash guard at the front of the engine. 2. Top engine cover is badly broken. 3. Rear drivers light is broken\cracked. 4. Possibly more importantly oil all over the sump, looks like it has run down from the dip stick perhaps? I call the garage and they say they will collect the car and drop off a courtesy car, 20 minutes later they call to say they have decided to send a transporter. I wait approximately 50 minutes, they drop off a car. While they are loading my car on to the transporter I see what was causing the loud chatter, the middle cover is flapping loose. My dilema is this, I gave them a perfectly good well looked after car which never gave me any trouble. They sold me this car saying it was the same and agreeing to do the 172 check and put on a 12 month Audi warranty. Am I wrong in thinking that given what they promised that I shouldnt have had to go over the car with a fine tooth comb, surely a condition of put on the warranty is that the car leaves their workshop in Audi approved condition. Lastly I tried to call the sales guy twice yesterday but he never returned my call. Any advice appreciated.