I have a 2017 GS A8. it shifts normally out of the garage, but when I take it to a show and it sits for a few hours and when I depart the show the 1st to 2nd gear shift has a very long shift lag, like it has a hard time getting into 2nd gear ( a very lazy shift). once this happens the car will shift normally unless it sits again for an hour or two.
has anyone experience this problem and know what the fix is? A GM tech at corvette at Carlisle said it maybe a hydraulic leak down on the 1st to 2nd gear cylinder when it sits for awhile. once the cylinder fills back up after the shift it shifts normally? he said take it to dealer for evaluation.
You are not alone. Many A8s experience this. Check the TSB listings and you will find one named Delayed Engagement. I believe this applies to your car. It is covered under powertrain warranty so don't wait. It will not get better. I have this issue. My 2015 is in the dealer right now. The transmission was replaced today and I expect to get it back tomorrow pending a good test drive. Good luck.