P0455 code

Thanks so much for your help. I was did a lot of research and found out that the vent valves go bad and they get stuck open. So when u run your truck it's supposed to be opened so the fumes can go through charcoal canister into the engine, and when u shot the truck off, the valve closes so the fumes don't get out. If the valve is bad it will remain opened, causing gas fume smell and throwing codes. I took mine valve off, blew it out with air, of course a lot of dirt came out, shook it and hear and felt that something was loose inside and rattle. Checked the voltage on the connector to make sure it has some, it was perfect. So I'm ordering a new valve online, when it gets here I will replace it and let u know if it worked.

Please do let me and everyone else in here know!

Now, how was the condition of the charcoal canisters? On mine the pellets were loose inside and they sounded like maracas...! I'm not sure if it was normal or not, and also had a nasty smell inside (like acid) and a yellow coating. I sprayed them with about 4 cans of Carburator cleaner and let them air dry before putting them back together. They came out really clean, but that didn't work at fixing the P0455 code.

That's another reason why I didn't get a new Vent Valve installed... I figured if the old Canisters were shot, (since I could not prove they were still good or not) then what was the point of getting a new Vent Valve! I couldn't figure out how to test the Vent Valve operation either since I don't have the proper tools and equipment. So I didn't want to waste money throwing parts at it.

Where did you get your Vent Valve from? Was it a Motorcraft OEM?

The canisters I wouldn't say we're in the best shape, it's a 2003 truck, and I doubt they were every replaced. But them going bad is a very low percentage. When they go bad all the charcoal would just pour it of the hole when u inspected them. It's just a charcoal filter, filters the fumes before they go into the engine. To test the valve u have to unplug the hose and turn the key on, don't start the truck just turn the key, and close the hole where u pulled the hose from with ur finger, u should feel some suction. if u don't feel it, it's stuck opened. At least that what I found online. But like I said I could tell it was bad just looking at it, it looked like it was from WW2. And it had a rattle. I got my new one from eBay oem for $45.

Well according to the Ford Workshop manual, this is the way to test the Vent Valve.
You need a Ford Scan Tool to be able operate the Vent Valve without running the engine.


SECTION 303-13: Evaporative Emissions

2003 Expedition/Navigator Workshop Manual

GENERAL PROCEDURES

Evaporative Emission System Leak Test

Special Tool(s)

Evaporative Emission System Tester 310-F007
(134-00056) or equivalent


Worldwide Diagnostic System (WDS)
418-F224,

New Generation STAR (NGS) Tester
418-F052, or equivalent scan tool


CAUTION: The evaporative emission system must not be pressurized to more than 3.48 kPa (14 inches H 2 O) or damage to the evaporative emission system may occur.

1. Connect the Evaporative Emission System Leak Tester to the evaporative emission test port.
2. Close the canister vent solenoid. For additional information, refer to Canister Vent Solenoid Closing Procedure in this section.
3. Pressurize the evaporative emission system to 3.48 kPa (14 inches H 2 O).
4. Monitor the system for two minutes. The system fails the leak test if the pressure falls below 2.0 kPa (8 inches H 2 O).
5. Repair any leaks as necessary.
6. Repeat the leak test until the system remains above 2.0 kPa (8 inches H 2 O) after the two-minute test period.

And this is to be done after repairs were to be performed... I just gave up on the whole thing!

SECTION 303-13: Evaporative Emissions
2003 Expedition/Navigator Workshop Manual
GENERAL PROCEDURES
Evaporative Emission Repair Verification Drive Cycle

Special Tool(s)

Worldwide Diagnostic System (WDS)
418-F224,

New Generation STAR (NGS) Tester
418-F052, or equivalent scan tool
Drive Cycle Recommendations

NOTE: The following procedure is designed to execute and complete the evaporative emission repair verification drive cycle and to clear the Ford P1000, inspection and maintenance (I/M) readiness code. When the ambient air temperature is below 4.4°C (40°F) or above 37.8°C (100°F), or the altitude is above 2,438 meters (8,000 feet), the EVAP monitor will not run. If the P1000 must be cleared in these conditions, the powertrain control module (PCM) must detect them once (twice on some applications) before the EVAP monitor can be bypassed and the P1000 cleared. The EVAP bypassing procedure is described in the following drive cycle.

1. Most OBD II monitors will complete more readily using a steady foot driving style during cruise or acceleration modes. Operating the throttle in a smooth fashion will minimize the time necessary for monitor completion.
2. Fuel tank level should be between one-half and three-quarters full with three-quarters full being the most desirable.
3. The evaporative monitor can only operate during the first 30 minutes of engine operation. When executing the procedure for this monitor, stay in part throttle mode and drive in a smooth fashion to minimize fuel slosh.

Drive Cycle Preparation

NOTE: For best results, follow each of the following steps as accurately as possible.

1. NOTE: This step bypasses the engine soak timer and resets OBD II monitor status.
   
   Install the scan tool. Turn the key ON with the engine OFF. Cycle the key off, then on. Select the appropriate vehicle and engine qualifier. Clear all diagnostic trouble codes (DTCs) and carry out a PCM reset.
2. Begin to monitor the following PIDs: ECT, EVAPDC, FLI (if available) and TP MODE. Press Diagnostic Data Link, PCM, PID/Data monitor and record, press trigger to select each PID, then start.
3. Start the engine without returning the key to the OFF position.

Preparation for Monitor Entry

WARNING: Strict observance of posted speed limits and attention to driving conditions are mandatory when proceeding through the following drive cycle.

1. NOTE: This step allows engine warm-up and provides intake air temperature (IAT) input to the PCM.
   Idle the vehicle for 15 seconds. Drive at 64 km/h (40 mph) until the ECT is at least 76.7°C (170°F).
2. Is IAT above 4.4°C (40°F) and below 37.8°C (100°F)? If not, continue with the following steps but note that the EVAP Monitor Bypass portion of the drive cycle (Step 13) will be required to bypass the EVAP monitor and clear the P1000.
3. NOTE: This step executes the heated oxygen sensor (HO2S) monitor.
   Cruise at 64 km/h (40 mph) for 60 seconds.
4. NOTE: This executes the EVAP monitor if IAT is above 4.4°C (40°F) and below 37.8°C (100°F).
5. NOTE: To initiate the monitor, TP MODE should equal PT, EVAPDC must be greater than 75%, and FLI must be between 15 and 85%.
6. NOTE: Avoid sharp turns and hills. Cruise at 72 to 104 km/h (45 to 65 mph) for 10 minutes.
7. NOTE: This step executes the ISC portion of the Secondary Air/CCM.
   Bring the vehicle to a stop. Idle with the transmission in DRIVE (for automatic transmission) or NEUTRAL (for manual transmission) for two minutes.

Pending Code and EVAP Monitor Bypass Check

NOTE: This determines if a pending code is preventing the clearing of P1000.
NOTE: If the EVAP monitor is not complete and IAT was below 4.4°C (40°F) or above 37.8°C (100°F) temperature range in Step 8, or the altitude is above 2,438 meters (8,000 feet), the EVAP Monitor Bypass (Step 13) must be carried out.
Using the scan tool, check for pending codes. Conduct normal repair procedures for any pending code concerns. Rerun any incomplete monitor.

EVAP Monitor Bypass

NOTE: This allows the bypass counter to increment to two.
NOTE: Do not repeat Step 4.

Park the vehicle for a minimum of eight hours. Repeat Steps 5 through 12.

Hope that info helps you solve your issue... please post back with your results when you get done.

Thanks for the info. The test you posted is the new evap test, but I hear that the smoke test is a lot better, but it cost about $100 to let a shop test it for you. Unless you want to buy your own smoke tester, which is between $600 to $1200, can't afford that. But I am looking up how to make your own smoke tester with a cheap fog machine, there's cheats for everything lol. My part should be here no later then Friday, July 29th, when it gets here I will replace it and let you know if that took care of it.

I replaced the DPFE Sensor and fixed the problem. Its a known issue with the 4.6L. There is an article on how to diagnose using a vacuum gauge and a multi meter. I'll try to find it.

This will tell you how to test most of your Evap system

http://easyautodiagnostics.com/ford/4.6L-5.4L/how-to-test-the-egr-system-1

Thanks for the info. Will definitely check it out when I'll get home.