Investigating the P0440 on Your 2022 Acura TLX
The P0440 code on your 2022 Acura TLX signals an EVAP system malfunction. Your sport sedan, available with the 2.0-liter turbo four-cylinder or the 3.0-liter turbo V6 (Type S), uses Honda/Acura's proven EVAP architecture. Let's investigate.
The TLX EVAP System
Both engine variants share the same EVAP fundamentals:
- Purge Control Solenoid Valve (PCSV) — Controls vapor flow from canister to intake
- Bypass Solenoid Valve — Honda-specific vapor routing
- Canister Vent Shut Valve — System sealing for leak tests
- Charcoal Canister — Vapor storage
- FTP Sensor — Fuel Tank Pressure monitoring
- Fuel Filler Cap — Twist-on with rubber gasket
Ranked Suspects
- Gas Cap Seal (29%) — Gasket wear after 2–3 years. Cost: $12–$25.
- Purge Control Solenoid Valve (24%) — Most common mechanical failure. Both turbo engines generate significant underhood heat. Cost: $35–$70, $110–$245 with labor.
- Bypass Solenoid Valve (16%) — Honda-specific component. Cost: $40–$80, $115–$255 with labor.
- Canister Vent Shut Valve (13%) — Sealing failure. Cost: $38–$75, $105–$240 with labor.
- EVAP Hose Issues (10%) — Turbo heat accelerates degradation. Cost: $10–$35, $75–$185 with labor.
- FTP Sensor (5%) — In-tank sensor. Cost: $45–$100, $120–$260 installed.
- Charcoal Canister (3%) — Overfilling. Cost: $85–$215, $180–$375 installed.
Diagnostic Steps
- Gas Cap — Inspect, clean, reseat or replace. Clear code and monitor.
- Companion Codes — P0441, P0442, P0446, P0497 (low purge flow).
- PCSV Test — Engine bay, verify with 12V power and vacuum pump.
- Bypass Solenoid — Test with HDS or compatible diagnostic tool.
- Smoke Test — $80–$150 for professional leak detection.
Warranty and DIY
Warranty: Acura's 4-year/50,000-mile warranty should still cover your 2022 TLX. The 6-year/70,000-mile powertrain extends further.
For DIY, the TLX's engine bay is more compact than SUV models, but the PCSV remains accessible from the top.
The Verdict
Your 2022 TLX's P0440 is most likely a gas cap or PCSV issue. Check warranty coverage — you should be fully covered for a free repair. Honda/Acura EVAP systems are reliable, and this is typically a one-time fix.