Have the OBDII ran, take it to a advanced auto parts to see if there is a code you may be running rich, or a number of other problems my Audi had a minor misfire which didn't flag the check engine light but caused an occasional backfire because the fuel was being exhausted. If the engine shudders it could be a misfire. Or its possible that your intake filter is clogged.
B7 Audi A4 C6 Audi A6 ~200kg
What oil does an Audi A4
1999 Audi a4 obd 2 conector problem
The 2014 Audi A4 has 16 valves.
The 2013 Audi A4 has 16 valves.
Where is the fuse panel on a 1997 Audi A4?
How do remove the headlights in a 2005 Audi A4?
The 2004 Audi A4 has 20 valves.
The 2005 Audi A4 has 20 valves.
The 2011 Audi A4 has 16 valves.
The 2001 Audi A4 has 20 valves.
The 2007 Audi A4 has 16 valves.