Investigating P0446 on Your 2022 Cadillac XT5
A P0446 code on your 2022 Cadillac XT5 indicates an EVAP vent control circuit malfunction. The XT5 uses the 2.0L turbocharged four-cylinder or 3.6L V6 on the C1XX platform with GM's standard vent valve solenoid. P0449 frequently accompanies P0446 as a GM-specific companion code targeting the same circuit.
The Cadillac basic warranty (4yr/50k) may still be active. The powertrain warranty (6yr/70k) extends through 2028.
Clues and Symptoms
- Check engine light with P0446
- P0449 companion code may be present
- Fuel fill difficulty
- EVAP readiness monitor incomplete
Top Suspects
- Vent Valve Solenoid Failure (High Likelihood): The primary P0446 component on GM vehicles. Replacement costs $130–$250.
- Vent Valve Wiring or Connector (High Likelihood): Connector corrosion from underbody exposure. Repair costs $80–$190.
- Purge Solenoid Valve (Medium Likelihood): Sticking purge valve disrupts EVAP flow. Replacement runs $110–$220.
- Charcoal Canister (Medium Likelihood): Canister degradation. Replacement costs $210–$380.
- Gas Cap Seal (Low Likelihood): Worn seal. Replacement is $15–$30.
How to Investigate
Scan for all codes. P0449 with P0446 confirms the vent valve solenoid circuit. A GDS2 scan at a Cadillac dealer provides commanded solenoid testing. For DIY, check the gas cap seal first, then inspect the vent valve connector.
Warranty and Cost
The Cadillac basic warranty (4yr/50k) may still apply. The powertrain warranty (6yr/70k) covers through 2028, and federal emissions warranty (8yr/80k) through 2030. Out of warranty: $130–$380.
Safe to Drive?
Yes. P0446 doesn't affect your XT5's engine, AWD, transmission, or any luxury features.