What is the cause of a rough idle in an Audi A5?

My Audi A5 has been experiencing a rough idle at stoplights. What could be causing this issue?

There are a few potential causes for a rough idle in an Audi A5. One possibility is a faulty oxygen sensor, which can affect the air-to-fuel ratio and cause rough idling. Another common issue is a dirty or clogged fuel injector, which can lead to inconsistent fuel delivery and result in rough idling. It's also possible that the spark plugs or ignition coils are failing, which can affect the engine's performance. It's recommended to have a professional mechanic diagnose the issue to determine the exact cause.

In addition to the potential causes mentioned above, another common culprit for rough idle in an Audi A5 is a dirty air filter. A clogged air filter can restrict air flow to the engine and cause it to run rough. I suggest checking your air filter and replacing it if it appears dirty or clogged.

I've had similar issues with my Audi A5 and found that my car was low on engine oil. Low oil levels can also contribute to rough idle as it affects the engine's lubrication and can cause it to run less smoothly. Be sure to regularly check and top off your engine oil to avoid this issue.