Solving the P0440 Mystery on Your 2022 Jeep Grand Cherokee
Your 2022 Jeep Grand Cherokee has set a P0440 code — an EVAP system malfunction. The all-new fifth-generation WL Grand Cherokee debuted for 2022 with a 3.6L Pentastar V6 (293 hp) or 5.7L Hemi V8 (357 hp), paired with an 8-speed automatic and available Quadra-Trac/Quadra-Drive 4WD. With a few years of service, EVAP components may be showing early wear. Let's investigate.
Symptoms
- Check engine light on
- Faint gasoline smell
- Slight MPG decrease
- Fueling difficulties
- Emissions test failure
Your Grand Cherokee drives normally. Engine, 8-speed, 4WD, and all luxury features are unaffected.
Most Likely Causes
- Gas Cap — Worn or loose. Check first. Estimated repair: $5–$25.
- Purge Solenoid Valve — Controls vapor flow to the engine. Can stick with age. Estimated repair: $80–$215.
- Vent Valve/Solenoid — Near the charcoal canister. Exposed to road conditions. Estimated repair: $90–$240.
- EVAP Hose Leak — Small cracks from heat cycling and road debris. Estimated repair: $50–$150.
- Fuel Tank Pressure Sensor — Can provide inaccurate readings. Estimated repair: $95–$250.
Diagnostic Steps
- Replace gas cap, clear code, drive 50+ miles
- Scan for companion EVAP codes
- Test purge and vent valves with scan tool
- Perform EVAP smoke test
- Inspect underbody components for road damage
Repair Costs
- Gas cap: $5–$25
- Purge solenoid: $80–$215
- Vent valve: $90–$240
- EVAP hose: $50–$150
- FTP sensor: $95–$250
- Diagnostic: $80–$150
Warranty: Jeep's 3-year/36,000-mile basic warranty has likely expired for a 2022 model. Check your purchase date and mileage.
Can I Drive With P0440?
Yes. No impact on performance, 4WD, or safety.
DIY Feasibility
Gas cap is trivial. The purge solenoid is moderately accessible in the engine bay on both the V6 and V8. The vent valve underneath is accessible thanks to the Grand Cherokee's ground clearance. DIY is moderate difficulty overall.