Cracking the P0440 Code on Your 2019 Jeep Cherokee
A P0440 code on your 2019 Jeep Cherokee points to an EVAP system malfunction. The KL-generation Cherokee came with a 2.4L Tigershark (180 hp), 3.2L Pentastar V6 (271 hp), or the 2.0L turbo (270 hp) for 2019. After 5-7 years of driving, age-related EVAP component wear is a real possibility. Let's follow the clues.
Symptoms
- Check engine light on
- Faint fuel smell, especially in warm weather
- Slight MPG decrease
- Fueling difficulties at the pump
- Emissions test failure
Your Cherokee drives normally. Engine, 9-speed automatic, and 4WD are unaffected.
Common Causes at This Age
- Worn Gas Cap Gasket — After 5+ years, the rubber seal degrades. Estimated repair: $5–$20.
- Purge Solenoid Valve — Controls vapor flow to the engine intake. Can stick or fail electrically at higher mileages. Estimated repair: $75–$200.
- Vent Valve/Solenoid — Age-related failure near the charcoal canister. Estimated repair: $85–$225.
- EVAP Hose Deterioration — Rubber vapor lines crack from years of heat cycling. Estimated repair: $45–$140.
- Charcoal Canister Saturation — Can degrade from overfilling or years of service. Estimated repair: $210–$470.
Diagnostic Steps
- Replace gas cap with OEM, clear code, drive 50+ miles
- Scan for companion EVAP codes (P0441, P0442, P0446, P0455, P0456)
- Test purge and vent valves with bidirectional scan tool
- Perform EVAP smoke test
- Inspect vapor hoses for visible cracking
Repair Costs
- Gas cap: $5–$20
- Purge solenoid: $75–$200
- Vent valve: $85–$225
- Vapor hose: $45–$140
- Charcoal canister: $210–$470
- Diagnostic: $80–$150
Warranty: Jeep's 3-year/36,000-mile basic warranty has expired. Check for any applicable recalls or extended coverage.
Can I Drive With P0440?
Yes. No performance or safety impact.
DIY Feasibility
Gas cap is trivial. The purge solenoid is moderately accessible in the engine bay on all three engines. The vent valve near the canister underneath requires more effort but is doable.