P0442

Low Severity

EVAP System Small Leak Detected

EVAP System

What Does P0442 Mean?

A small leak in the EVAP system, often a deteriorated gas cap seal or a tiny crack in a hose.

Common Fix

Replace gas cap

Estimated Cost (DIY)

$5 - $15

Symptoms

  • ⚠️Check engine light
  • ⚠️No driveability symptoms
  • ⚠️Failed emissions test

Related Symptoms

Check engine light on

Common Causes

Deteriorated gas cap seallikely
Small crack in EVAP hosepossible
Loose hose connectionpossible
Cracked charcoal canisterunlikely

How to Diagnose P0442

  1. 1Replace gas cap (cheapest fix)
  2. 2If code returns, smoke test EVAP system to find leak
  3. 3Inspect all EVAP hoses and connections
  4. 4Check canister and purge valve

OEM Diagnostic Flowchart

Scroll to load technician if/then branches.

Read live data and freeze frame for P0442 to pinpoint the cause before buying parts.

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Related Resources

Repair guides, symptom pages, and wiring diagrams related to P0442.

OEM Manual Evidence

Browse →
2013 GMC Truck Yukon XL Denali AWD V8-6.2L A L L Diagnostic Trouble Codes ( DTC )OEM Manual

A L L Diagnostic Trouble Codes ( DTC ) — 2013 GMC Truck Yukon XL Denali AWD V8-6.2L Service Manual | Operation CHARM Operation CHARM : Car...

2013 GMC Truck Yukon XL Denali 2WD V8-6.2L A L L Diagnostic Trouble Codes ( DTC )OEM Manual

A L L Diagnostic Trouble Codes ( DTC ) — 2013 GMC Truck Yukon XL Denali 2WD V8-6.2L Service Manual | Operation CHARM Operation CHARM : Car...

2013 GMC Truck Yukon XL 4WD V8-6.0L A L L Diagnostic Trouble Codes ( DTC )OEM Manual

A L L Diagnostic Trouble Codes ( DTC ) — 2013 GMC Truck Yukon XL 4WD V8-6.0L Service Manual | Operation CHARM Operation CHARM : Car repair...

2013 GMC Truck Yukon XL 4WD V8-5.3L A L L Diagnostic Trouble Codes ( DTC )OEM Manual

A L L Diagnostic Trouble Codes ( DTC ) — 2013 GMC Truck Yukon XL 4WD V8-5.3L Service Manual | Operation CHARM Operation CHARM : Car repair...

Related Symptoms

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Check engine light onSymptom Hub

A check-engine light is a graph entry point into code pages, symptom-specific diagnosis, and the exact repair categories most often associated with those failures.

Exact Vehicle Hubs

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2013 Gmc Truck Yukon Xl 4wd V8 5.3l Repair HubManual

Open the exact vehicle hub grounded by OEM manual evidence related to P0442.

2013 Gmc Truck Yukon Xl 4wd V8 6.0l Repair HubManual

Open the exact vehicle hub grounded by OEM manual evidence related to P0442.

2013 Gmc Truck Yukon Xl Denali 2wd V8 6.2l Repair HubManual

Open the exact vehicle hub grounded by OEM manual evidence related to P0442.

2013 Gmc Truck Yukon Xl Denali Awd V8 6.2l Repair HubManual

Open the exact vehicle hub grounded by OEM manual evidence related to P0442.

Related Codes

P0440: EVAP System MalfunctionRelated

General EVAP system fault — the system that captures fuel vapors is not working properly.

P0455: EVAP System Large Leak DetectedRelated

A significant leak in the EVAP system. Often a loose gas cap or a disconnected hose.

P0456: EVAP System Very Small Leak DetectedRelated

A very small leak in the EVAP system — smaller than P0442.

Frequently Asked Questions

Is P0442 serious?
Not at all — there is zero effect on driveability. It only matters for emissions testing.
Can P0442 go away on its own?
Sometimes — if the gas cap was not fully tightened, tightening it and driving for a few days may clear it.

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