2021 Audi P0303: What It Means & Is It Safe to Drive?
P0303 on the 2021 Audi: Cylinder 3 Misfire Detected. Here's what it means, what usually causes it, what repairs typically cost, and whether it's safe to keep driving.
What this code means
The PCM has detected a misfire specifically on cylinder 3. Diagnosis follows the same steps as P0301—swap parts to the same position on a known-good cylinder to isolate the fault.
Common causes on the 2021 Audi
- Worn or fouled spark plug on cylinder 3
- Failing ignition coil on cylinder 3
- Leaking or clogged fuel injector
- Low compression on cylinder 3
Symptoms
- Check Engine Light, often flashing under load
- Rough idle or shaking
- Loss of power, hesitation
Typical fixes
- Replace spark plug and coil on cylinder 3
- Test and replace fuel injector
- Compression test if ignition parts don't resolve it
Repair cost range
For a 2021 Audi, repairs for P0303 typically fall between $150 and $900, depending on the root cause and labor rates in your area.
Known issues on Audi
Audi 3.0T TFSI supercharged V6 P0303 (rear bank, cylinder 3) often comes from a failed ignition coil or injector. The 3.0T's FSI direct injection causes less carbon than lower-RPM applications. On the 4.2L FSI V8, cylinder 3 coil failures are common past 80k miles.
Most commonly affected models