I'd say
8A8ACan turn up in Audi or BMW. (5)[-----] is missing a subject in its definition, so you should probably change that to "It can turn up"?
Also,
1A1ARaft error gives further back. (5)[-----] and
10A10ATiled shift gives nasal glyph. (5)[-----] use "gives" as an anagram indicator, which is pretty weak, since it doesn't really indicate any sense of chaos or rearrangement. I don't have suggestions for changes, but just keep in mind for future puzzles to check how well your indicators work. (It's often helpful to draw from examples, so here are some resources for wordplay indicators:
https://www.crosswordunclued.com/2008/09/dictionary.html https://bestforpuzzles.com/cryptic-crossword-dictionary/)