Seeing the P1442 code on your OBD2 scanner? This common Nissan/Infiniti-specific code means the EVAP system has detected a small leak of 0.040" (1 mm) or larger in the fuel vapor containment system.
While it rarely causes drivability issues, ignoring it will cause failed emissions tests and may trigger the check engine light permanently.
In this detailed guide, we’ll cover everything about the P1442 EVAP small leak detected – from meaning and causes to symptoms, diagnosis steps, and fixes. We’ll also show how professional tools like the iCarsoft CR Ultra P make troubleshooting faster and more accurate.
What Does P1442 Mean?
P1442 is a Nissan/Infiniti manufacturer-specific code that translates to “EVAP Canister System – Small Leak Detected (Positive Pressure)” or “Leak Detected in EVAP Control System (0.040 inch)”.
The ECM performs a leak test by pressurizing the EVAP system. If it detects a leak ≥ 0.040", it sets P1442.
Related searches: P1442 Nissan small EVAP leak causes and fixes, how to diagnose P1442 0.040 leak on Infiniti G35 G37.
Common Symptoms of P1442
- Illuminated Check Engine Light (CEL)
- Failed emissions/smog test (EVAP monitor incomplete)
- Occasional fuel smell (rare)
- Difficulty filling gas tank in some cases
Top Causes of P1442 Code
- Loose, missing, or damaged gas cap (by far the most common)
- Cracked or disconnected EVAP hoses (especially purge valve & vent valve hoses)
- Faulty EVAP purge volume control solenoid valve
- Faulty EVAP canister vent control valve (see our P1446 guide)
- Leaking fuel tank or filler neck
- Cracked charcoal canister
How to Diagnose P1442 Step-by-Step
Use a professional scanner that can run the full EVAP leak test and actuate components.
Best Tool for Accurate P1442 Diagnosis: iCarsoft CR Ultra P
Basic code readers only show the code. The iCarsoft CR Ultra P is a professional multi-brand diagnostic tablet that supports:
- Over 200 vehicle brands worldwide (1996–2025+ models)
- Full Nissan/Infiniti enhanced diagnostics including EVAP system leak test, purge valve & vent valve bi-directional control
- Live data graphing on Altima, Maxima, Pathfinder, Frontier, Rogue, Sentra, G35, G37, Q50, Q60, FX, QX56 and thousands more
- Advanced coverage for Japanese, European, American brands
- Bi-directional control, ECU coding, 41+ service functions
- J2534, DoIP, CanFD support for newest 2025 models
- 10" touchscreen, Wi-Fi updates, 3 years free software
Users clear P1442 EVAP small leak detected in minutes after pinpointing the exact leaking hose or faulty valve.
Get iCarsoft CR Ultra P Now – Fix P1442 Fast
How to Fix P1442 (Repair Options)
| Step | Action | Approx. Cost |
|---|---|---|
| 1 | Tighten or replace gas cap | $0–$35 |
| 2 | Replace cracked EVAP hoses | $50–$200 |
| 3 | Replace purge or vent control valve | $120–$350 |
| 4 | Smoke test + repair leaks | $150–$600 |
| 5 | Replace charcoal canister (rare) | $400–$900 |
Frequently Asked Questions (FAQ) About P1442
Is P1442 serious? Can I drive with it?
No drivability risk, but you'll fail emissions and may release fuel vapors into the atmosphere.
Will P1442 clear itself?
Only if the leak is fixed (e.g., tightening the gas cap) and you complete several drive cycles.
Most common vehicles that throw P1442?
Nissan Altima (2002–2013), Sentra, Maxima, Pathfinder, Frontier; Infiniti G35, G37, QX56, FX35/45/50 – especially after 100k miles.
Best OBD2 scanner for Nissan EVAP testing?
The iCarsoft CR Ultra P – full enhanced diagnostics and bi-directional EVAP tests at a fraction of dealer tool cost.
How much does it cost to fix P1442 at a shop?
$80–$800 depending on whether it’s just a gas cap or a full smoke test + hose replacement.
Ready to diagnose and clear P1442 accurately on your Nissan or Infiniti? Get the iCarsoft CR Ultra P and save hundreds on dealer visits.
