When your 2022 BMW 3 Series displays the P0305 code, the diagnostic approach depends on your engine configuration. The 2022 3 Series offers four-cylinder and inline-six options. P0305 is valid on the M340i's inline-six but anomalous on four-cylinder 330i/330e models.
2022 3 Series Engine Options
The 2022 3 Series offers the 2.0L B48 turbo I-4 (255 hp in 330i) and the 3.0L B58 turbo I-6 (382 hp in M340i). Only the inline-six has cylinder 5.
Inline-Six Diagnosis
On the B58, cylinder 5 is toward the rear. Common causes include spark plug wear, ignition coil failure, and direct-injection carbon buildup on intake valves.
Four-Cylinder Models
If your 3 Series has the 2.0L turbo, P0305 is anomalous. Investigate ECM issues.
Diagnostic Steps
Verify engine type. Use BMW diagnostic equipment. On inline-six, inspect cylinder 5 components. On four-cylinder, check for diagnostic errors.