P0440

Low Severity

EVAP System Malfunction

EVAP System

What Does P0440 Mean?

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

Common Fix

Replace gas cap

Estimated Cost (DIY)

$5 - $15

Symptoms

  • ⚠️Check engine light
  • ⚠️Faint fuel smell possible
  • ⚠️Failed emissions test

Related Symptoms

Check engine light on

Common Causes

Loose or cracked gas caplikely
EVAP canister purge valve faultpossible
EVAP vent valve faultpossible
Cracked EVAP hosepossible

How to Diagnose P0440

  1. 1Tighten gas cap and clear code
  2. 2If code returns, inspect gas cap seal
  3. 3Check purge and vent valves
  4. 4Smoke test EVAP system

OEM Diagnostic Flowchart

Scroll to load technician if/then branches.

Read live data and freeze frame for P0440 to pinpoint the cause before buying parts.

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Related Resources

Repair guides, symptom pages, and wiring diagrams related to P0440.

OEM Manual Evidence

Browse →
2013 Dodge Avenger L4-2.4L A L L Diagnostic Trouble Codes ( DTC )OEM Manual

A L L Diagnostic Trouble Codes ( DTC ) — 2013 Dodge Avenger L4-2.4L Service Manual | Operation CHARM Operation CHARM : Car repair manuals f...

2013 Dodge Avenger V6-3.6L A L L Diagnostic Trouble Codes ( DTC )OEM Manual

A L L Diagnostic Trouble Codes ( DTC ) — 2013 Dodge Avenger V6-3.6L Service Manual | Operation CHARM Operation CHARM : Car repair manuals f...

2013 Chrysler 200 V6-3.6L A L L Diagnostic Trouble Codes ( DTC )OEM Manual

A L L Diagnostic Trouble Codes ( DTC ) — 2013 Chrysler 200 V6-3.6L Service Manual | Operation CHARM Operation CHARM : Car repair manuals fo...

2013 Chrysler 200 L4-2.4L A L L Diagnostic Trouble Codes ( DTC )OEM Manual

A L L Diagnostic Trouble Codes ( DTC ) — 2013 Chrysler 200 L4-2.4L Service Manual | Operation CHARM Operation CHARM : Car repair manuals fo...

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 Chrysler 200 L4 2.4l Repair HubManual

Open the exact vehicle hub grounded by OEM manual evidence related to P0440.

2013 Chrysler 200 V6 3.6l Repair HubManual

Open the exact vehicle hub grounded by OEM manual evidence related to P0440.

2013 Dodge Avenger L4 2.4l Repair HubManual

Open the exact vehicle hub grounded by OEM manual evidence related to P0440.

2013 Dodge Avenger V6 3.6l Repair HubManual

Open the exact vehicle hub grounded by OEM manual evidence related to P0440.

Related Codes

P0441: EVAP System Incorrect Purge FlowRelated

The EVAP purge flow is not within expected range.

P0442: EVAP System Small Leak DetectedRelated

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

P0455: EVAP System Large Leak DetectedRelated

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

Frequently Asked Questions

What is the EVAP system?
The EVAP system captures fuel vapors from the tank and routes them to the engine to be burned, preventing pollution.
Can a loose gas cap cause P0440?
Yes — the #1 cause of EVAP codes is a loose, cracked, or missing gas cap. Tighten it and clear the code.

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