Saturday, June 16, 2012

2003 Dodge Grand Caravan: OBD Error Code P0456?

Check Engine light Code P0456.

This code is occurred due to many reasons.Proper troubleshooting is required.

The P0456 is "EVAP System Small Leak Detected". This is actually a very hard one to diagnose, as there are many things that can set this code.
To start your troubleshooting to clear this code from your vehicles computer memory ,
First, check the Fuel Cap and make sure it is tight.
Also properly inspect the underside of the cap for any defects that may keep it from sealing tightly.
If there are any doubts or cap looks dirty ,old and worn out - replace the cap.

Please note,use branded parts. You'll need a cap that meets Dodge specs. Those "universal" or "discount" caps they sell at AutoZone will not seal the system.

But Now we Assume that  cap is  good, and no problems, the next part to look at is the EVAP Purge Solenoid.
For this carefully inspect the vacuum lines to the solenoid for any cracks, holes or loose/missing connections. The solenid should then be tested for proper operation. If the Purge Solenoid checks ok, the next item to look into is the Leak Detection Pump (aka NVLD Pump). Again, inspect the vacuum lines and test for functionality.
Most commonly, this will be a faulty fuel cap or the Purge Solenoid,
but please be aware that there are many items in the EVAP (emissions control) System, that when faulty, set the P0456 error code and there needs to be a lot of testing done to find the actual culprit.

One more thing  with this error code, the vehicle will not show any symptoms, as this is a fault in the Emissions system, and will not effect engine performance in any way at all.The Engine will perform absolutely fine in most of cases.

See the parts diagram shown below.This will show you which parts to be checked and where tare they located:--------
EVAP Assembly dodge

Also see the Leak detection pump location:--------

leak detection pump NVLD

In some cases you will notice that Disconnecting the battery cables for few minutes then reconnecting the cable helps to reset the system and error code clears and engine light turns off.But this will not help in all cases.The light will come Back again.

The reason the light goes out when  the battery cables are removed, is this does a "code clear". It's like "re-booting" the on-board computer. Once the on-board computer resets, and re-checks all the systems, it will find the problem again, and the engine light WILL return. This is known as a "drive cycle" and usually takes 50-75 miles of city/highway driving. When the light returns, you will need to look into the Purge Solenoid and NVLD as stated above.

This details will help.

Users Who Viewed This Problem Also Viewed:

Evaporative Emissions System codes details?


2005 Scion XB: Evaporator coil Replacing?


EVAP connecting hose to PCV valve Collapse?


2002 Nissan/Datsun Pathfinder: Location for EVAP Purge Valve Solenoid?



How to disconnect the hose form the Evap Canister?

2004 Chrysler PT Cruiser: Location of EVAP Purge Solenoid Valve?


For All types of Car models and brands help 
Go to Newly Launched

FREE Car repair guide? 

Complete Car repair Help FREE? 

No comments:

Post a Comment