Dodge Ram code PO456, where is the Evap Canister

Steve Allison

• 5569 Answers
• Posted on Mar 06, 2009

SOURCE: Evaporative emission system - small leak/no BB flow condition

Although I recommend you buy a Haynes service manual for your Dodge, I think you will find the canister attached to the firewall or one of the fender wells. Most of them look a lot like an overgrown spam can and it will have two connections on it.

Mike Butler

• 6674 Answers
• Posted on May 31, 2009

SOURCE: trouble code po456 evap small leak ? could it be the gas cap ?

Can't say 100% obviously, but quite often that is the cure, but try to take some time to make sure all your hoses , in the system are in good shape & tight.

SOURCE: Evap leak

your caravan has a system to control fumes from the gas tank .. any evaporating fuel is absorbed into a canister .. that is connected to a evap/purge solenoid in the engine compartment that directs the fumes to be burned in the engine once its running .. .. the problem can be as simple as a damaged or leaking or wrong type gas cap .. if the gas cap doesnt seal well then air can be drawn into the evaporitive control system ... also if any of the hoses from the evap/purge solenoid to the canister (located near the gas tank) are cracked or loose, you will get the same results .. some of these hoses are rubber .. some are hard plastic .. sometimes they come loose at the canister and need a clamp added ... the evap/purge solenoid could also be bad but much more likely the gas cap is just bad, bent or wrong ..

SOURCE: 03 grand caravan ex 3.8. check engine light - code

Customer Concern: MIL on and code P0456 for a leak in the evaporative system. How to test the Leak Detection Pump (LDP). Tests/Procedures: 1. With the engine running, connect a test light to the Violet/White wire at the LDP. The test light should light.

2. Ground the center wire at the LDP. The test light should go out. This is the intake stroke of the pump. The LDP pulls in fresh air when the center wire is grounded with a vacuum supply to the LDP.

3. Remove the ground from the center wire and the test light should light up again. The pump has just pumped air into the evaporative system. The test light lights up when the diaphragm is in the down position.

4. To test the LDP for leaks, cap off the port that goes to the canister or to the vent valve. This is the port that is slightly above the bottom port that goes to the vent filter.

5. Now try to cycle the LDP again by grounding the center wire. The test light will still go out but now when the ground is removed from the center wire, the test light should remain out for at least 20 seconds if the LDP is good. Potential Causes: Leak Detection Pump (LDP)
Vent Valve

SOURCE: 01 dodge ram 1500 5.2 4WD code P0455 evap system leak.

This code will not stall or no start of your engine, evap only work when engine is off, it is to reduce the fume your gas tank lets out to protect the o zone, but it will not pass Emission test, also could be some thing a small as your gas cap not sealing right.