P0442 on Your 2024 Acura MDX
A P0442 code on your 2024 Acura MDX points to a small evaporative emission system leak. On a brand-new luxury SUV, this is typically a minor issue with your Acura warranty covering the repair completely.
EVAP System
The 2024 MDX uses Honda/Acura's standard EVAP system with a bypass solenoid valve, canister vent shut valve, and charcoal canister. The PCM detects leaks by monitoring pressure decay equivalent to approximately 0.020 inches.
Likely Causes
- Gas cap not fully seated (45%) — The most common trigger on newer vehicles. Honda/Acura systems are particularly sensitive to cap seal quality.
- Gasket contamination (20%) — Debris on the cap seal.
- EVAP connection looseness (15%) — A factory fitting that vibrated loose.
- Bypass solenoid valve defect (10%) — A rare factory defect.
- Canister vent shut valve defect (10%) — A manufacturing imperfection.
What to Do
Reseat your gas cap firmly. If the code persists, visit your Acura dealer. HDS diagnostics provide comprehensive EVAP testing. All repairs are warranty-covered.
Costs ($0 Under Warranty)
- Gas cap: $20–$45
- EVAP hose repair: $90–$250
- Bypass solenoid valve: $130–$300
- Canister vent shut valve: $120–$280
Warranty
Your 2024 MDX is covered under Acura's 4-year/50,000-mile basic warranty, 6-year/70,000-mile powertrain warranty, and federal 8-year/80,000-mile emissions warranty. All P0442 repairs are free.