P0440 Nissan Sentra
EVAP System Malfunction · Powertrain Code · Low · Repair: Easy
What is P0440?
General EVAP (evaporative emission control) system malfunction. The system that prevents fuel vapors from escaping has detected a fault.
When the Nissan Sentra triggers code P0440 (evap system malfunction), it typically points to an issue in the powertrain system. Below you'll find the most common causes, symptoms, and repair options specific to the Nissan Sentra.
This repair is rated easy, meaning basic tools, no lift needed.
Diagnostic data on this page is compiled from publicly available repair resources and technical service bulletins. Always have a qualified mechanic confirm the diagnosis before authorizing repairs on your Nissan Sentra.
Common Causes on Nissan Sentra
- Loose or damaged fuel cap
- Cracked EVAP canister (common on Nissan)
- Failed EVAP purge volume control valve
- Leaking EVAP system hose or connector
Symptoms
- Check Engine Light on
- Fuel odor near vehicle
- No driveability symptoms
Notes for Nissan Sentra
Nissan EVAP systems are sensitive to small leaks; always start with a fuel cap check and visual inspection.