Technical Definition:

Evaporative Emission System Vent Control Circuit Intermittent

Technical Description:

Possible Causes:

Possible Symptoms:

Evaporative Emission Control System Vent Valve/Solenoid Circuit Malfunction

Possible Solutions:

OBD-II Trouble Code Type:

Diagnostic Step:

Tech Notes:

– Purge Control Valve harness is open or shorted
– Purge Control Valve electrical circuit poor connection
– Faulty canister vent control valve

Specific Makes:

Technical Definition:

Evaporative Emission System Vent Control Circuit Shorted

Technical Description:

Possible Causes:

Possible Symptoms:

Evaporative Emission Control System Vent Control Circuit Close

Possible Solutions:

OBD-II Trouble Code Type:

Diagnostic Step:

Tech Notes:

– Faulty canister vent control valve
– Purge Control Valve harness is open or shorted
– Purge Control Valve electrical circuit poor connection

Specific Makes:

Technical Definition:

Evaporative Emission System Vent Control Circuit Open

Technical Description:

Possible Causes:

Possible Symptoms:

Evaporative Emission Control System Vent Control Circuit Open

Possible Solutions:

OBD-II Trouble Code Type:

Diagnostic Step:

Tech Notes:

– Faulty canister vent control valve
– Purge Control Valve harness is open or shorted
– Purge Control Valve electrical circuit poor connection

Specific Makes:

Technical Definition:

Evaporative Emission System Vent Control Circuit

Technical Description:

Possible Causes:

• Faulty vent valve
• Open, short or excessive resistance on Vent valve control circuit
• Blockage of vent valve
• Bad PCM

Possible Symptoms:

Evaporative Emission Control System Vent Control Circuit Malfunction

Possible Solutions:

• Replace Vent valve
• Repair open, short, or resistance problem in control circuit
• Repair open, or short, or resistance problem in power circuit
• Replace PCM

OBD-II Trouble Code Type:

Diagnostic Step:

Tech Notes:

– Missing Fuel cap
– Incorrect fuel filler cap used
– Fuel filler cap remains open or fails to close
– Foreign matter caught in fuel filler cap
– Vent control valve harness is open or shorted
– Vent control valve circuit poor electrical connection
– Faulty vent control valve

Specific Makes:

– Possible a noticeable fuel odor caused by the release of fuel vapors

Technical Definition:

Evaporative Emission System Purge Control Valve Circuit Shorted

Technical Description:

Possible Causes:

Possible Symptoms:

Evaporative Emission Control System Purge Control Valve Circuit Shorted

Possible Solutions:

OBD-II Trouble Code Type:

Diagnostic Step:

Tech Notes:

– Faulty Evaporative Emission (EVAP) Purge Solenoid Control
– Evaporative Emission (EVAP) Purge Solenoid Control harness is open or shorted
– Evaporative Emission (EVAP) Purge Solenoid Control circuit poor electrical connection

Specific Makes:

Technical Definition:

Evaporative Emission System Purge Control Valve Circuit Open

Technical Description:

Possible Causes:

Possible Symptoms:

Evaporative Emission Control System Purge Control Valve Circuit Open

Possible Solutions:

OBD-II Trouble Code Type:

Diagnostic Step:

Tech Notes:

– Faulty Evaporative Emission (EVAP) Purge Solenoid Control
– Evaporative Emission (EVAP) Purge Solenoid Control harness is open or shorted
– Evaporative Emission (EVAP) Purge Solenoid Control circuit poor electrical connection

Specific Makes:

Technical Definition:

Evaporative Emission System Purge Control Valve Circuit

Technical Description:

Possible Causes:

• Bad purge solenoid (internal short or open)
• Wiring harness chafing or rubbing another component causing short or open on control circuit
• Connector worn, broken or shorted due to water intrusion
• Driver circuit inside powertrain control module (PCM) is bad

Possible Symptoms:

Evaporative Emission Control System Purge Control Valve Circuit Malfunction

Possible Solutions:

• Using a scan tool, command the purge solenoid to activate. Listen or feel for a clicking coming from the purge solenoid. It should click once, or on some models it may click repeatedly.
• If it doesn’t click with scan tool activation, unplug the connector and examing the solenoid and connector for damage, water, etc. Then check for battery voltage on the feed wire with the key on. If you have battery voltage, then ground the control side manually using a jumper wire and see if the valve clicks. If it does, then you know the solenoid is working properly but there is a problem with the control circuit. If it doesn’t click when you manually ground it, replace the purge solenoid.
• To check for a problem on the control circuit (if the solenoid tests okay and you have voltage to the solenoid) plug the solenoid back in and remove the control circuit (ground) wire from the ECM connector (If you’re unsure how to do this, do not attempt). With the ground wire removed from the ECM, turn the key on and then manually ground the Purge valve control wire. The solenoid should click. If it does, then you know there is no problem with the control wire to the solenoid and there is a problem with the ECM purge solenoid driver circuit in the ECM. You’ll need a new ECM. However if it doesn’t click, then there must be an open in the wiring between the ECM and and the solenoid. You must find it and repair it.

OBD-II Trouble Code Type:

Diagnostic Step:

Tech Notes:

– Faulty Evaporative Emission (EVAP) Purge Solenoid Control
– Evaporative Emission (EVAP) Purge Solenoid Control harness is open or shorted
– Evaporative Emission (EVAP) Purge Solenoid Control circuit poor electrical connection

Specific Makes:

Technical Definition:

Evaporative Emission System Leak Detected (small leak)

Technical Description:

Possible Causes:

A loose or improperly affixed gas cap
A non-conforming gas cap (i.e. not factory/original brand)
A small leak/hole in a fuel vapor hose/tube
Other small leak in EVAP system
Faulty vent o-ring seal
Defective vent valve
Defective purge valve
Defective leak detection pump

Possible Symptoms:

• The only thing you will notice is the Malfunction Indicator Lamp (MIL) a.k.a.
• Check Engine Light will be illuminated.
• You likely won’t notice any drivability problems although sometimes a fuel odor may be noticed.

Evaporative Emission Control System Leak Detected Small Leak

Possible Solutions:

• Remove and reinstall the gas cap, clear the codes, and drive for a day and see if the codes come back.
• Otherwise, replace the gas cap (we recommend an OEM not aftermarket part), or
• Inspect the EVAP system for cuts/holes in tubes/hoses

OBD-II Trouble Code Type:

Diagnostic Step:

• Using an advanced scan tool, perform an EVAP leak test
• Verify operation of the EVAP purge solenoid / valve
• Perform a smoke test to see where the leak is
• Generally there are vehicle and model specific procedures for proper diagnosis of this DTC.

Tech Notes:

– Missing or loose fuel cap
– Incorrect fuel filler cap used
– Fuel filler cap remains open or fails to close
– Foreign matter caught in fuel filler cap
– EVAP canister or fuel tank leaks
– EVAP system hose leaking
– Fuel tank leaking

Specific Makes:

– Possible a noticeable fuel odor caused by the release of fuel vapors

Technical Definition:

Evaporative Emission System Incorrect Purge Flow

Technical Description:

This indicates that a part of the EVAP control system is no longer functioning correctly. The EVAP system consists of many parts, including (but not limited to) the gas cap, fuel lines, carbon canister, purge valve, and other hoses. The (EVAP) emission control system prevents the escape of fuel vapors from a vehicle’s fuel system. Fuel vapors are routed by hoses to a charcoal canister for storage. Later, when the engine is running a purge control valve opens allowing intake vacuum to siphon the fuel vapors into the engine.

Possible Causes:

• Bad vacuum switch
• Broken or damaged EVAP line or canister
• Open in PCM purge command circuit
• Open or short in Voltage feed circuit to Purge Solenoid
• Faulty purge solenoid
• Restriction in EVAP solenoid, line or canister
• Corrosion or resistance in purge connector
• Bad PCM

Possible Symptoms:

Evaporative Emission Control System Incorrect Purge Flow

Possible Solutions:

• Common Chrysler fix – Replace Leak Detection Pump / LDP
• Repair damaged EVAP lines or canister
• Repair open or short in voltage feed circuit to Purge Solenoid
• Repair open in PCM purge command circuit
• Replace purge Solenoid
• Replace vacuum switch
• Repair restriction in Evap line or canister or solenoid
• Repair resistance in purge connector
• Replace PCM

OBD-II Trouble Code Type:

Diagnostic Step:

Tech Notes:

– Missing Fuel cap
– Incorrect fuel filler cap used
– Fuel filler cap remains open or fails to close
– Foreign matter caught in fuel filler cap
– Incorrect fuel tank vacuum relief valve

Specific Makes:

– Possible a noticeable fuel odor caused by the release of fuel vapors

Technical Definition:

Evaporative Emission System

Technical Description:

This indicates that a part of the EVAP control system is no longer fuctioning correctly. The EVAP system consists of many parts, including (but not limited to) the gas cap, fuel lines, carbon canister, purge valve, and other hoses

Possible Causes:

• The gas cap is not installed or working properly
• The purge solenoid has failed
• The canister is plugged and not working properly

Possible Symptoms:

Evaporative Emission Control System Malfunction

Possible Solutions:

• Remove and reinstall the gas cap, clear the code, and drive for a day and see if the codes come back.
• Inspect the EVAP system for cuts/holes in tubes/hoses
• Inspect for damaged or disconnected hoses around the Evap purge solenoid
• Check and/or replace the sensor
• Check and/or replace the purge valve
• Have a professional use a smoke machine to detect leaks

OBD-II Trouble Code Type:

Diagnostic Step:

Tech Notes:

– Missing or loose fuel cap
– Incorrect fuel filler cap used
– Fuel filler cap remains open or fails to close
– Foreign matter caught in fuel filler cap
– EVAP canister or fuel tank leaks
– EVAP system hose leaking
– Fuel tank leaking

Specific Makes:

– Possible a noticeable fuel odor caused by the release of fuel vapors