On our Compass I had to sand the filler neck contact surface to remove a layer of corrosion and unevenness. The CEL hasn't come on since.I oiled the sanded part and the o-ring on the cap. I didn't look up your code definition.

 

+1 ^ ^
I had this intermittent evap code on the Caliber years ago. The filler neck rim where the gas cap rubber o-ring seal seats against it had a rough, rusted surface.
I lightly sanded the filler neck contact surface and smeared a layer of silicone grease on the gas cap rubber o-ring seal.
It hasn't happened since.

 

Thanks.
I checked the filler pipe and it was pristine, not a speck of rust, and had a flat black coating all over it. So I didn't sand anything.

But I checked before I removed the cap, still got the P0441 code. I removed the cap and put a thin bead of silicone caliper guide lubricant around the cap's O-ring and on the mating surface, and just a tiny smear on the threads, and put the cap on.

I checked the codes twice in a row, and the P0441 was gone - only showed "dONe".

So time will tell if the code really cleared completely, and I'm all set, or if it only is not visible with the key dance, and is still stored in the computer where an inspector could read it. I would hope that if it's gone from the key dance display, it's really gone; but it's possible that the history is stored still. But so far, so good.

 

I found a previous discussion about this intermittent issue. Post #12, Nov 29, 2017.

P0441 evap code (at https://www.allpar.com/forums/threads/p0441-evap-code.160343/ )

P0441 is set when the PCM attempts to purge the canister of vapors and inject them into the intake manifold. It has an expected purge vapor ratio which should be attained but the actual vapor ratio is not matching the target ratio. Code P0441 is set. The evaporative purge test is only ran after a successful pass for the large leak test and small leak test. So you can rule out a fuel cap or evaporative emission hose leak in the system.

This is a schematic of the emission system on your vehicle with ESIM / evaporative system integrety monitor device and other emission control equipment.

Note item #4 in the schematic which is the fresh air filter. When the evaporative purge test is instigated, fresh air must move through this filter and into the evaporative canister. In the canister it picks up trapped vapors from the canister vapor containment and carries them forward, through the purge valve and into the intake manifold. Now if this filter is plugged there will be a restriction. The PCM will pulse the purge solenoid to get a higher flow volume but this possible obstruction could be preventing that from happening. The PCM sets code P0441.

Now this is just an "educated guess" on my part but a possible cause. The vapor canister and filter are located near a rear wheel where dust and debris are more prevalent. GM has had problems with the fresh air vent for its emission system becoming clogged on its 1500 Silverado pickups because of its location on the truck body. So check that fresh air filter near the vapor canister and its hose for obstructions.

 

If the canister were cracked, or a hose damaged, would that make it fail? Since the vapors being pulled in would be leaned out by the leak?

 

. . . . If the canister were cracked, or a hose damaged, would that make it fail? Since the vapors being pulled in would be leaned out by the leak? . . . .

Various service manuals and online discussions about code P0441 indicate that the PCM pulses the purge solenoid at a certain rate. However the resultant vapor flow as determined by the oxygen sensor and other devices is not close to the expected target rate. No indication is given if the discrepancy is high or low. My suggestion of a plugged fresh air filter would cause a lower than expected vapor flow rate. But your suggestion of a cracked canister or hose would cause less restriction and too high a flow rate??? I definitely think your thought is entirely possible.

You could connect a bi-directional scan tool and force the PCM to pulse the purge solenoid with engine idling. With all devices intact you would expect the upstream oxygen sensor to read rich and the short term fuel trim to go very negative (taking away fuel) as extra fuel vapors are introduced into the intake system. So if the vapor canister is cracked and you perform the same test would the oxygen sensor read lean and the short term fuel trim go positive to compensate????

 

Reason I suggest the leak is that this car was rear-ended twice. Very minor hit, but enough to replace the bumper fascia the first time.

 

I should also mention that the dealer replaced the fuel pump under warranty at 11 months and 10,500 miles, so they probably had to drop the tank. They might have screwed up something related to this system when they did. They replaced the fuel pump because the gas gauge would intermittently plunge to zero, then up again about 30 seconds later. They then 'cleaned contacts at the instrument cluster' a few months later, but the gauge was still acting up. Finally a few weeks after that, they 'tightened a very loose ground wire at instrument cluster' and the gauge problem went away permanently.

If the pump for this circuit is near the filler pipe or fuel tank, as I think it is, maybe they disrupted something when they replaced the fuel pump. It was about 9 months and 7K miles later that I experienced the P0441 code.

Where is the vapor canister on this car? And the filter for the system?

 

. . . .I should also mention that the dealer replaced the fuel pump under warranty at 11 months and 10,500 miles, so they probably had to drop the tank. They might have screwed up something related to this system when they did. . . . .

To start the purge test and possibly setting code P0441 the evaporative system MUST PASS both the large leak and small leak test. So when the PCM runs the test for purge flow in the vapor canister there are NO LEAKS in the evaporative emission system (includes the vapor canister). So this issue is not caused by previous maintenance activity. Below is a synopsis of theory of operation on the test for purging vapors from the evaporative canister.

The Evap Purge Monitor tests the integrity of the hoses/tube between the throttle body/intake and the fuel tank. The
monitor is a two stage test and runs only after the Evap system passes the small leak test. Stage one is nonintrusive.
The PCM monitors the purge vapor ratio and the ESM switch closed ratio. If the purge vapor ratio is
above a calculated value, the monitor passes. If the ESM switch closed ratio is greater than calculated value when
purge flow is greater than a minimum value, the monitor passes. Stage two is an intrusive test and runs only if
stage one does not pass. The PCM commands the purge solenoid to flow at a specified rate to force the purge
vapor ratio to update. The ratio is compared to a calibrated specification. If it is less than specified, a one trip failure
is recorded. This test can detect if the purge hose is off, obstructed, or the purge valve is not operational.
² When Monitored:
With the engine running, after the Evap System small leak test has passed.
² Set Condition:
If the PCM detects that the purge vapor ratio and the ESM switch closed ratio are below a calculated value,
the PCM commands the purge solenoid to flow at a specified rate to update the purge vapor ratio. If the ratio
remains below a specified value, a one trip failure is recorded. Two Trip Fault. Three good trips to turn off the
MIL.

Possible Causes

INTERMITTENT DTC
EVAP PURGE SOLENOID VACUUM SUPPLY
EVAP PURGE HOSE/TUBE OBSTRUCTION
EVAP PURGE SOLENOID
POWERTRAIN CONTROL MODULE (PCM)

In the highlighted theory of operation the PCM is pulsing the purge solenoid at a duty cycle less than 100%. If the system is functioning properly air drawn through the fresh air filter and into the vapor canister picks up hydrocarbon vapors. This travels through the vapor line to the purge solenoid and is ingested into the engine air intake. This fuel rich vapor should cause the oxygen sensor to go rich and, in turn, cause the short term fuel trim to go negative. I believe this is not happening and the PCM is setting code P0441.

It is also possible that the purge solenoid is sticking and not oscillating properly when it is subjected to a pulsing duty cycle by the PCM. A more accurate way to monitor behavior is to use a bi-directional scan tool to force the PCM to activate the purge solenoid on a duty cycle. Then you monitor the oxygen sensor value and short term fuel trim values to see if the expected behavior described occurs.

I suggested checking the fresh air filter as it must not be obstructed so as to allow proper air flow for the purge operation to occur. Without a scan tool to use I thought this the next best thing to check. Code P0441 is indicating that the purge air flow is not optimal. You do not know if the test air flow is too high or too low. I am guessing it is too low due to a restriction in the fresh air filter.

. . . Where is the vapor canister on this car? And the filter for the system?

This is a video showing the location of the vapor canister on a 2007 Sebring which is a close cousin of the 2012 Chrysler 200 model. Go to time interval 02:05.

View: https://www.youtube.com/watch?v=NYOXfs0OgiQ


Attached is an image of the vapor canister and its components.

On the 2007 Sebring / 2008 Avenger models the fuel pump module was accessible from the cabin of the vehicle. I will assume that was carried forward on later models. You remove the rear seat bottom cushion and there is a large rubber plug in the floor pan. Remove the plug and you see the top of the fuel tank and the fuel pump module. You can inspect and see if there is anything awry with vapor hoses and lines at the pump module.

 

One thought, when you fill the gas tank, do you top off the tank squeezing in a few extra shots of gas or do you just remove the fill handle after it trips off? If you top off the tank some liquid gas may be pushed into the vapor canister. When the purge cycle is activated, liquid gas is pulled rather than vapor which could lead to rough running (rich fuel mixture) or codes being set.

 

It's my wife's car, she never tops it off. She stops as soon as it clicks off, every time. Has always run perfectly its entire life.

 

From what I have seen a P0441 is due to a blockage (not leak) in the purge system or a tank pressure sensor not reporting the proper change. Look for a bad purge solenoid, restricted hose to the purge solenoid or between the purge and the tank. With a DVOM hooked up to the FTP sensor, monitor the change in voltage during evap test. Could also be a problem with the ESIM switch.

 

. . . .From what I have seen a P0441 is due to a blockage (not leak) in the purge system or a tank pressure sensor not reporting the proper change. Look for a bad purge solenoid, restricted hose to the purge solenoid or between the purge and the tank. With a DVOM hooked up to the FTP sensor, monitor the change in voltage during evap test. Could also be a problem with the ESIM switch. . . . .

The schematic I referenced in post #6 does not show a FTP (fuel tank pressure) sensor as of year 2012. So there is no direct way to monitor slight pressure changes within the tank. Has Chrysler engineering started to use an FTP sensor after year 2012 on its vehicles?

. . . Is the air filter something I can buy if I need one? . . . .

I did a search for "Chrysler fuel vapor vent" and found this. You will have to compare and see if this is the correct part and identical to the device on your vehicle. For an initial test I would disconnect the existing filter and blow air in the reverse direction and see how much debris is released. Reinstall and test.

 

The cannister on the Compass is behind the LR wheel house.

 

OK, so I didn't have time to fully check it out tonight. But I did slide under on my creeper and wipe dirt on my polo shirt.

I did not see any damage or cracks or disconnects on anything. However, I pushed on all the hoses where they connect, and the thicker one at the vapor canister gave a faint 'click' and moved just a tiny bit further on, maybe a couple of millimeters. I pushed and pulled back and forth to check for play, and it did not click again at all, and there was no noticeable play. So it's possible that that hose was not quite 100% engaged on the canister.
I didn't have time to jack up the car and remove the air filter and blow through it and the hoses, but I inspected as much as I could see, and all appeared good. I also looked underhood and the purge solenoid looked good, and the hoses and electrical plug were on tight and looked OK.

I didn't want to open the garage door and do a cold start just to check. If it's now good, it will clear. If it didn't, it won't clear. Either way, doing a cold start unnecessarily would not buy us anything. Tomorrow my wife will be driving it, and will find out then if it clears.

I also have to do my usual pre-inspection check of tires, wipers, lights, horn, etc.

 

. . . I didn't have time to jack up the car and remove the air filter and blow through it and the hoses, but I inspected as much as I could see, and all appeared good. I also looked underhood and the purge solenoid looked good, and the hoses and electrical plug were on tight and looked OK. . . .

For this specific code P0441 a visual inspection of the purge solenoid will not provide any valid information. There could be an internal problem in the purge solenoid that prevents it from providing proper flow through the vapor canister.

. . . I didn't want to open the garage door and do a cold start just to check. If it's now good, it will clear. If it didn't, it won't clear. Either way, doing a cold start unnecessarily would not buy us anything. Tomorrow my wife will be driving it, and will find out then if it clears.
. . . .

It may take many days of driving before the PCM clears this code if the offending situation is no longer present. It takes 2 trips to set the code and absence of the code setting parameters for 3 trips before the code is erased from PCM memory. One trip is defined as vehicle setting unused for several hours and engine cooling to ambient temperature and then started and driven again.

 

Right, I wasn't saying it would clear the first time. I looked at the solenoid, canister and hoses just to see if there was visible damage, not as a diagnostic. Last time, it cleared in less than 5 days.

 

So...my wife used the car today, cold start, and the CEL was on the whole time. About a 10-mile round trip, one hot start coming back from the destination.
We used the car about 2 hours later, again a 'cold start' according to the gauge. No CEL. Drove about 25 miles. Cold start leaving there 3 hours later, no CEL. Got home and checked twice in a row - no codes stored.

Time will tell, but for now, it's cleared.

 

. . .I did not see any damage or cracks or disconnects on anything. However, I pushed on all the hoses where they connect, and the thicker one at the vapor canister gave a faint 'click' and moved just a tiny bit further on, maybe a couple of millimeters. I pushed and pulled back and forth to check for play, and it did not click again at all, and there was no noticeable play. So it's possible that that hose was not quite 100% engaged on the canister. . . . .

Which thicker hose did you push and get an audible click? A - vapor line connecting tank to canister? B - fresh air vent filter to canister? See attached image.

. . . So my wife used the car today, cold start, and the CEL was on the whole time. About a 10-mile round trip, one hot start coming back from the destination.
We used the car about 2 hours later, again a 'cold start' according to the gauge. No CEL. Drove about 25 miles. Cold start leaving there 3 hours later, no CEL. Got home and checked twice in a row - no codes stored.

Time will tell, but for now, it's cleared. . . .

I am certainly interested in your follow up on this issue. Making an evaporative system line more secure resolves an evaporative code problem????

 

It was the thicker one that goes to the gas tank. Line A, at the canister.

 

. . . It was the thicker one that goes to the gas tank. Line A, at the canister. . . . .

So that "A" line in the diagram is the evaporative line that connects top side of fuel tank to vapor canister. As the tank is filled with fuel hydrocarbon vapors exit through this line and are absorbed by the vapor canister.

Documentation for diagnostic code P0441 indicates that when the PCM runs the vapor purge test and a deficiency is found, this code is set, The large leak and small leak test have run and passed. But the operator made the line more secure by pushing it onto and latching it on its port on the vapor canister. That would tend to indicate a small evaporative leak was corrected???

Hmmm. The diagnostic information is missing some information. If this fixes the problem and code P0441 does not return, then the PCM was doing a small leak test in conjunction with a vapor purge test and set a vapor purge code P0441 which was caused by a small leak. At least that is my theory.

Chrysler must have an engineer tucked away in a hidden place where air and sunlight are piped in. He/she wears a beanie with propeller on top and their sole purpose in life is to right obscure and complicated software tests for emissions compliance.

 

Today my wife drove a 7-mile round trip with one shutoff and hot start. Then a hour later, she drove to a store 5 miles away, then a mile from there, then home.
The CEL and P0441 are still gone. I don't know what to say. I hope it's gone forever, but I won't assume that since it has plagued us about 15 times almost since new, for the last 7 years.

 

. . . .The CEL and P0441 are still gone. I don't know what to say. I hope it's gone forever, but I won't assume that since it has plagued us about 15 times almost since new, for the last 7 years. . . .

Keep monitoring and continue with follow up. That is the only way one can get ahead and become knowledgeable of the quirks of modern automotive technology. Glad you did NOT fire the "parts cannon" which would have been frustrating and expensive.

 

Well, that was a short-lived victory.

CEL came on a day after tanking up. Next trip, light was out. Haven't had a chance to do the key dance yet.

Will have to check the air filter, hoses and solenoid someday when I get a chance. But at least we got our annual inspection sticker last week while the light was out and codes clear.

 

. . . CEL came on a day after tanking up. Next trip, light was out. Haven't had a chance to do the key dance yet.

Will have to check the air filter, hoses and solenoid someday when I get a chance. . . .

Obviously an intermittent condition to just drive you crazy with trying to find a remedy. At least you do not have the pressure to get it fixed immediately.

I did some research and found more information about the code P0441 and purge ratio failure to meet minimum value. Since year 2007 U S environmental regulations require that manufacturers must have active purge monitors that verify that the vapor canister will hold hydocarbon vapors and flow air to purge and burn them in the engine. The purge ratio is the amount of hydrocarbons in the air flow as a percentage of the total airflow entering the engine. It does this by increasing the purge valve duty cycle beyond the minimum acceptable ratio value and looking for expected changes in the air - fuel ratio reported by the oxygen sensor and the short term fuel trim value. If the purge ratio does not increase beyond the minimum value the PCM will assume there is no air flowing into the canister and set code P0441. This could mean a leaking or obstructed purge hose, a stuck or intermittent or sluggish purge valve or a clogged air filter on the vent tube to the vapor canister.

At this point I would suggest to continue driving the vehicle and just observe if the situation gets worse. You are going into the summer months with higher temperatures and heat load on the engine so that may or may not make a difference. Hopefully the situation will get worse and maybe a component will fail absolutely and then you will be able to easily identify the culprit.

Here is the link I found and used to base my comments.

Chrysler EVAP Performance Codes - Automotive Service Professional (at https://www.autoserviceprofessional.com/article/97410/chrysler-evap-performance-codes )

Side note (opinion):
I am starting to understand how a technician or DIY person with knowledge and a logical, methodical mind set accompanied with a hi-tech, feature filled, bi-directional scan tool can make short work of diagnosing these types of conditions. On page 11 of the reference article, the author indicates to use a bi-directional scan tool with engine running. You activate the purge monitor and watch the air-fuel ratio and oxygen sensor values change. If they remain low then you know where to check in the system as mentioned as there is an air flow restriction or purge valve problem.

Trying to "poor boy" solutions and avoid the sophisticated tools leads to lots of frustration with guessing and work arounds. But is anyone ready to make the leap and purchase a not so inexpensive scan tool and commit oneself to the education it would require??? I am not at that point yet.

 

No code is stored, and a successive trip had no CEL.

 

It's been doing this since it was a year old, and it does happen any month of the year, but more often in warm weather. It's unlikely to fail outright having done this maybe 12-15 times over the last 7 years. So I'll just need a weekend when I can crawl under it when it's elevated safely and check each component.