P0456 on Your 2024 Audi Q7
A P0456 code on your 2024 Audi Q7 indicates the ECM has found a very small leak (0.020-inch equivalent) in the EVAP system. Your Q7 uses the VW Group's LDP and N80 purge valve EVAP architecture. On a new model, this is typically minor and fully warranty-covered.
Whether your Q7 features the 2.0L turbo four or the 3.0L turbo V6, the EVAP system is the same across all variants.
Likely Causes
- Gas cap not fully seated (33%) — Most common cause. Click firmly.
- Software calibration sensitivity (22%) — ECM updates may adjust thresholds.
- Factory EVAP connection variance (18%) — A fitting not fully engaged.
- N80 purge valve irregularity (15%) — A marginal component.
- LDP variance (7%) — A marginal reading.
- New seal break-in (5%) — Fresh seals needing cycling.
What to Do
- Check the gas cap — Remove, inspect, reinstall.
- Audi dealer visit — Full warranty, zero cost. ODIS diagnostics and TSB check.
- Software update and physical repair — Dealer handles everything.
Cost
- Under warranty: $0—covered through 2028 (basic) and 2032 (emissions)
- Gas cap (DIY): $15–$40
Warranty
Your 2024 Q7 carries Audi's 4-year/50,000-mile basic warranty through 2028 and federal emissions coverage for 8 years/80,000 miles through 2032. Take it to the dealer at no cost.