P0441Powertrain
Powertrain · SAE
EVAP System — Incorrect Purge Flow
Meaning
The ECU detects that the fuel vapor flow through the purge valve does not match the expected value. Flow may be absent, insufficient, or excessive relative to the commanded duty cycle.
Common causes
- EVAP purge valve clogged or stuck closed
- Hose between canister and purge valve blocked, kinked, or disconnected
- Purge valve stuck open (excessive flow)
- Saturated charcoal canister not releasing vapors correctly
- Leak in the EVAP circuit altering the flow measurement
Symptoms
- Malfunction indicator lamp (MIL) on
- Possible rough idle or torque surges on rapid throttle opening (if valve stuck open)
- Fuel odor in the cabin or engine bay
- Elevated evaporative hydrocarbon emissions
- Sometimes no noticeable driveability symptoms
Severity
Moderate: the engine runs normally but evaporative emissions exceed regulatory limits and the condition may worsen over time.
What to do
- Check purge valve response with a scan tool using forced actuation
- Inspect EVAP hoses between canister and purge valve for blockages, cracks, or disconnections
- Measure purge valve coil resistance (typically 22–32 Ω)
- Inspect the charcoal canister for saturation or physical damage
- Replace the purge valve if it does not respond correctly to forced actuation