The P1447 code is a Nissan/Infiniti-specific fault that means the ECM commanded the EVAP purge valve open but detected no purge flow from the charcoal canister to the engine.
In 95% of cases the purge control solenoid valve (located on or near the intake manifold) is mechanically stuck closed or electrically failed.
What Exactly Does P1447 Mean?
During normal driving, the ECM opens the purge valve to burn stored fuel vapors. If it sees no change in fuel trim or manifold vacuum when the valve is commanded open, it sets P1447 – “EVAP Control System Purge Flow Monitoring” fault.
Long-tail keywords: P1447 Nissan purge valve stuck closed fix, Infiniti G37 Q50 P1447 EVAP purge flow monitor repair 2025.
Common Symptoms of P1447
- Check Engine Light on
- Failed emissions test (EVAP monitor incomplete)
- Slight fuel smell near engine bay (rare)
- Rough idle or hesitation when warm (if valve is completely blocked)
- No major drivability issues in most cases
Most Common Causes
- Faulty EVAP purge volume control solenoid valve (Nissan part 14930-xxx)
- Clogged or cracked purge hose from canister to valve
- Blocked charcoal canister (often combined with P1446/P1442)
- Electrical issue – blown fuse, open circuit, bad connector
- Rare: ECM software or vacuum leak after the valve
Step-by-Step Diagnosis
- Scan with a tool that can command the purge valve on/off
- Listen for audible click from the valve when commanded
- Apply 12V directly to the valve → should click and allow airflow
- Check vacuum hoses for cracks or disconnection
- Perform smoke test if needed
Best Diagnostic Tool for P1447 in 2025: iCarsoft CR Ultra P
Generic scanners cannot actuate the purge valve on Nissan/Infiniti. The iCarsoft CR Ultra P professional tablet gives you:
- Full bi-directional control of EVAP purge valve & vent valve
- Live data & graphing for purge duty cycle and fuel trim
- Perfect coverage for Altima, Maxima, Sentra, Rogue, Pathfinder, Frontier, Murano, G35/G37, Q50/Q60, QX56/QX80, Titan, Armada and all 1996–2025+ models
- Topology mapping, 41+ service functions, ECU coding
Get iCarsoft CR Ultra P – Fix P1447 in Minutes
Typical Repair Costs
| Repair | Average Cost (Parts + Labor) |
|---|---|
| Replace purge control solenoid valve | $140–$380 |
| Replace purge hose(s) | $80–$250 |
| Purge valve + charcoal canister | $550–$950 |
Frequently Asked Questions (FAQ) – P1447
Can I drive with P1447?
Yes, usually no performance loss, but you’ll fail emissions and may have minor idle issues.
Most common vehicles that get P1447?
Nissan Altima (2002–2013), Maxima, Sentra, Rogue; Infiniti G35, G37, Q50, QX56 – especially in warm/humid regions where the valve sticks more often.
Can I clean the purge valve instead of replacing it?
Sometimes – spray carb cleaner through it while actuating, but replacement is far more reliable.
Best scanner for Nissan EVAP bi-directional tests?
iCarsoft CR Ultra P – full Nissan/Infiniti enhanced diagnostics and active tests for a fraction of the Nissan Consult price.
External resource: OBD-Codes.com P1447
