EVAP System Flow During Non-Purge (Nissan) / EVAP Incorrect Purge Flow (Toyota)
What does P1441 mean?
The P1441 code means the vehicle's onboard diagnostic system has detected: EVAP System Flow During Non-Purge (Nissan) / EVAP Incorrect Purge Flow (Toyota). This is a low severity code.
Common Symptoms
- Check Engine Light on
- Fuel smell from engine bay or near gas tank
- Rough idle when cold
- Slight hesitation at startup
- Failed emissions test
Probable Causes (Ranked by Likelihood)
- EVAP purge valve stuck open Very High
- Leaking or cracked EVAP hose High
- Failed EVAP canister vent valve Moderate
- Saturated charcoal canister Moderate
- Gas cap not sealing properly Low
Step-by-Step Diagnostic Procedure
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Check the EVAP purge valve -- command it closed and verify no vacuum passes through
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Inspect all EVAP hoses for cracks, disconnections, or damage
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Test the EVAP canister vent valve for proper operation
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Check if the charcoal canister is saturated -- look for fuel odor
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Verify gas cap is tightened and sealing properly
Frequently Asked Questions
Can I drive with code P1441?
Yes. This is an EVAP system code that primarily affects emissions. The vehicle will drive normally, but you may fail an emissions test and notice a fuel smell.
What causes P1441?
A stuck-open purge valve is the most common cause. It allows fuel vapors to enter the engine when they should not, causing a rich condition at idle. EVAP hose leaks are also common.
Can a gas cap cause P1441?
While unlikely to be the primary cause, a loose or damaged gas cap can contribute to EVAP system problems. Always check the gas cap first as it is the simplest and cheapest potential fix.