AutoCodes
 
OBDII Code List
 
P2421 DODGE

P2421 DODGE - Evaporative Emission System Vent Valve Stuck Open

Repair Importance Level: 3/3
Repair Difficulty Level: 2/3   
Comments  |  Add Comment

Possible causes

  • Faulty Evaporative Emission Vent Shut Valve
  • Evaporative Emission Vent Shut Valve harness is open or shorted
  • Evaporative Emission Vent Shut Valve circuit poor electrical connection

Possible symptoms

  • Engine Light ON (or Service Engine Soon Warning Light)

P2421 Dodge Description

The fuel tank pressure (FTP) sensor output indicates about atmospheric pressure 0 kPa (0 in.Hg, 0 mmHg) before purge starts since the evaporative emission (EVAP) canister vent shut valve is normally open (open to the atmosphere). The sensor indicates a negative pressure value (vacuum) during purging.

When the FTP sensor indicates vacuum after starting the engine, there is the possibility of an FTP sensor zero point shift failure or an EVAP canister vent shut valve stuck closed failure. So the powertrain control module (PCM) monitors the FTP sensor output after purge starts. The PCM detects a malfunction of the EVAP canister vent shut valve if the output indicates excessive vacuum.

However, if the fuel tank internal pressure is below the specified value (excessive vacuum is detected) when starting the engine, the malfunction detection should be done as follows because it is difficult to distinguish the FTP sensor range problem (P1454) from the EVAP canister vent shut valve stuck closed (P2422).

1. If neither Temporary Diagnostic Trouble Code (DTC) (P1454 nor P2422) is stored, both DTCs are stored.

2. If both Temporary DTCs (P1454 and P2422) are stored and excessive vacuum is detected, both DTCs are stored.

3. If either Temporary DTC (P1454 or P2422) is stored and excessive vacuum is detected, the PCM stores the DTC of the Temporary DTC that was stored.

OBDII Code P2421 Dodge - Evaporative Emission System Vent Valve Stuck Open - AutoCodes.com

Need more help?

Get the P2421 Dodge code diagnosed by a professional: Find a repair shop in your area

Related Information

P2421 DODGE Comments

Help us improve AutoCodes.com. Leave a comment below or tell us if the information above help you fix the code. What are the symptoms on your vehicle for the P2421 Dodge code? Have you replaced any parts?
Any information is appreciated. Thanks
Top ⇧