A flickering check engine light with a rough idle usually means active misfires. Here’s what to check first and when to stop driving.
What a flickering check engine light really means
On your Audi Q3 II, a check engine light that flickers or flashes is different from a steady light. It almost always points to an active misfire — one or more cylinders are not burning fuel correctly. That raw fuel can overheat and destroy the catalytic converter, so this is the one CEL pattern you should not ignore. A rough idle often accompanies it because the engine is trying to run on fewer than all cylinders, especially when warm or cold.
