Checking the exhaust system for leaks (Audi A3 8L)

On vehicles with a variable catalytic conversion, a leak in the exhaust system before the oxygen sensor can cause the following problems:

• Difficulties with starting; the engine stalls, runs unevenly at idle, and jerks when the speed increases.

Execution order

1. Start the engine and cover the muffler with a rag or plug.

2. Listen carefully to the exhaust system for leaks. If necessary, spray the cylinder head/exhaust manifold and exhaust manifold/downpipe connections with "Leck Sucher" and check if bubbles appear.

3. Fix the leak.

[This article was copied from the website AUDImanual]