P144C Fault Code

[gatzdon]

Just got back from a 4500 mile road trip and only 50 miles from home I get a check engine light. I pull the code and get

P144C

Searching the internet seems to indicate the EVAP Check Valve or EVAP Purge Valve. At the moment, I'm leaning towards trusting this article the most which indicates that the code is for the Check Valve.

http://www.tomorrowstechnician.com/under-the-hood-ford-engines-big-things-come-from-small-packages/

Because of the pressurized intake system on a turbo engine, the EVAP purge system has a mechanical check valve added between the intake manifold and the purge valve.

The PCM tests the check valve each drive cycle by monitoring the fuel tank pressure sensor for a raise in pressure while the engine is under minimal boost. If the fuel tank pressure sensor reports a raise above a preset threshold, DTC P144C (EVAP check valve performance) is set.

If this code is set, the PCM may shut down turbo operation to protect the EVAP system and fuel tank from damage.​

I now have 49,400 miles on the vehicle and as far as I can tell, this is not covered by the emissions warranty.

Has anyone else experienced this yet? I want to make sure this isn't covered by some warranty before I clear the code.

 

[cwescapexlt4x4]

I had the EVAP Purge Valve go out on mine and yes, threw the CEL and have rough idle.
Mine was covered under the CPO warranty, but not sure about your situation.

 

[gatzdon]

Just wanted to share with everyone what I have found so far. Seems the latest info I could find on DTC P144C is as follows.

P144C - Evaporative Emission System Purge Check Valve Performance
Description:
The EVAP check valve test is performed during minimal boost conditions, once per drive cycle, when entry conditions are met. This DTC sets when the fuel tank pressure exceeds a calibrated amount within a specified amount of time during the test.
Possible Causes:
 Restricted EVAP ejector connections at the intake air system
 Stuck open EVAP check valve
 Stuck closed EVAP check valve
 Damaged EVAP ejector
 Damaged EVAP check valve​

The short term result of ignoring this code is that turbo may be disabled. If the check valve is failing, this could result in true over pressurization of the fuel tank.

Turns out there is a TSB on the 2012 Explorer which covers the possible cause "Restricted EVAP ejector connections at the intake air system". TSB instructions state to use a 5mm drill bit to ensure that the port is clear of any plastic flashing that shouldn't be there. That's the first thing I will check when I get a chance.

If that's not the problem, I will probably decide if I should invest in hand vacuum pump test kit to test the purge valve (check valve is part of the purge valve), or I may just replace the purge valve and cross my fingers. From what I can see online, a vacuum test of the purge valve is pretty quick, easy, and accurate (you just need the right tool to do it).

As for the EVAP ejector, I'm not familiar with that yet, but if it's not the purge valve, I guess I will be getting familiar with that real quick.

 

[gatzdon]

Well, got through the first check. I disconnected the EVAP line from the Air Intake Duct. I didn't have a 5.0mm drill bit, but I did have a 3/16" drill bit (about 4.8mm). I did have to rotate the drill bit to get it to pass through.

Thinking I didn't want to leave plastic shavings in the intake duct, I did remove the intake duct to clean out the inside. I have attached pics of the top of the engine, the port with the drill bit in it, and the inside of the port. Hoping this helps someone else.

I saved all the freeze frame data, then cleared the codes. Turns out P144C is a permanent code, so it will stay in memory until the vehicle successfully tests the condition again.

The Freeze Frame data indicated that the EVAP Pressure was 32.78 inches of water at the time (this is about 1.2 psi). Idling in the driveway, the EVAP Pressure was reading around negative 32 inches of water.

EVAP Port with Drill Bit
Top of Engine
EVAP Port inside Air Intake Duct

edit: corrected Fuel Tank Pressure to EVAP Pressure. Don't think they are the same and I don't seem to have access to the Fuel Tank Pressure with the software that I have.

 

[gatzdon]

Final update on mine, and hope this thread saves someone money.

With the 3/16" drill bit, I did clean out some plastic flashing from the EVAP port on the air intake duct. I didn't realize I can remove mine before I cleared the flashing, but with a flat head screwdriver, you can remove the intake duct and inspect the inside before cleaning it out.

P144C is considered a permanent code. This means that even if you reset your DTC's, the code will remain in history until the vehicle is able to retest for the condition. After about a week, the historical code finally cleared.

A little about the EVAP tests that I wish I knew before I topped off my gas tank. The vehicle will not run the EVAP monitor tests unless the following conditions are met. Intake Air Temperature between 40 and 90 degrees Fahrenheit and Fuel Tank Level is between 25% and 75%. Ranges may be a little wider, but that's the recommendation to ensure that they run. Also, many of the monitor tests won't run unless the Intake Air Temperature and Engine Coolant Temperature are close to each other at startup (recommended 8 hours cooldown). Last, 5-10 minutes at 45mph with cruise control, then 5-10 minutes at 55mph with cruise control will cause most of the EVAP monitor tests to complete. Usually 2 monitor tests are required for the computer to report that the monitor tests are complete.

Last, Forscan now has a Lite Android version (may have an iphone too?) for less than $5 in the app store. This app lets you see quite a bit of the Ford specific information on your vehicle, including the status for all the individual monitor tests (The evap monitor has almost a dozen individual tests), so you can at least see if you really fixed your problem, or if the computer just hasn't retested for the condition yet.

The Forscan Lite has also allowed me to see all the communication errors going on with my Power Steering System and my HVAC system. I'm hoping that these are normal and this is a case of too much information for my own good.

Bottom line, P144C did not require a new EVAP Purge Valve or a new EVAP Check Valve to fix. Hope I save someone else money and time.

 

[Rschmeck1]

Gatzdon, well said, my 12 Explorer's plastic flashing EVAP hole was plugged exactly as you described, so I took off the intake duct, drilled it out, cleaned out the debris, and the CEL went off two days later. Thanks for saving me $$.

Regarding the communication errors from your Power Steering system, last week I had my dealer flash the PCM software and while he was doing that he noticed Ford had a warrantied and required flash on the Power steering software so maybe flashing that (aka updating the power steering software) would help. Not sure...

Question - do you ever clean, or worry about, the documented carbon buildup "issue" on the backside of the cylinder #2 and #3 intake valves? Apparently its a prob with these EB's...though the Ford dealer downplays it, calls it a non-issue. I'll check for another thread on this but thought I'd ask, you seem to know your stuff. Thanks.

 

[peterk9]

........Regarding the communication errors from your Power Steering system, last week I had my dealer flash the PCM software and while he was doing that he noticed Ford had a warrantied and required flash on the Power steering software so maybe flashing that (aka updating the power steering software) would help. Not sure.......

There are several posts saying the software update for the steering issue does not fix it. The only fix is to replace the steering rack.

Peter

 

[Woah322]

My CEl was on for a bit with P144C, never seen a code ending in a letter and multiple OBD2 scanners said no dtc definition but appears to be the same EVAP / purge valve issue. Had the dealer fix under the extended warranty last week.