Hey everybody,
So my check engine light came on and the code P0441 came up on the code checker which was "incorrect purge flow". I checked all the hoses and lines that seemed as if they were involved and they all seemed fine. There were no cracks or bad connections. I replaced the purge solenoid which didn't seem to fix anything (so i returned it). Being the optimist I am, i tried tightening my gas cap which unfortunately didn't work. The only other thing I can think would need replacement is the vapor canister, but I don't want to do that unless I know i need to. Does anyone have any ideas of how to fix this or how to check if the vapor canister needs replacing?
Thanks in advance,
Shane

 

It could be one of a number of things. I think P0441 is for a small evap leak. Tightening the gas cap won't do much good if the seal on the gas cap is bad. You can try a new gas cap, some say use only an OEM cap but I can say I replaced my gas cap over 2 years ago with one from the parts store and it is still doing fine.

There is kind of a common problem with the hoses at the charcoal canister under the driver's side of the truck. The hoses are known to crack and split. Also the canister itself can go bad, especially if you "top off" the tank after the gas pump shuts off when you fill up. I do not know how to test the canister.

It could also be the emissions leak detection pump, if you have one. Maybe it is best to start with the cheapest solution first. A new gas cap costs about $10.00 at the parts store. Maybe replace it, clear the code and see if it comes back. When I replaced my own gas cap I could smell gas fumes in the area of the gas fill flap, that was how I knew it was bad.

Jimmy

 

I would check the hoses first. It's a known issue. Be ware that one is tricky- I think it's 5/8 at one end and 3/4 at the other, and it's a formed hose.

 

Not sure what the year is, but it could be the NLVD pump by the rear canister.

 

I've checked all the hoses that seem like they're involved with the EVAP system and none of them are cracked where I can see. Unless they have a crack between the solenoid and the canister, I'll check that tomorrow.

And Markk96, I have an 02 Dakota V6. Would the NLVD pump be by the canister or on top of the fuel tank?

I'll try a new gas cap tomorrow and if that doesn't work I'll try a new leak detection pump. I'm trying my damnedest to not buy a new canister but if that's what it comes down to, that's what it comes down to.

 

The leak detection pump is mounted to the bottom side of the battery tray. It is kind of a pain to get the tray out, but it is not too hard of a job. It has emissions hoses too, so it would be worth a look to see if they are cracked. The smallest slightest crack in a hose is still enough to set the P044xx code.

The gas vapor canister usually only goes bad if you are prone to add more gas in the tank after the handle clicks off when filling up. I think it is best to start with the simplest and cheapest solution first, try a new gas cap, clear the code, drive the truck a few days and see if the code comes back. Gas caps do go bad fairly often, there is a seal in the cap that fails with age and it does not take much of a fuel vapor leak to set the code.

The P044xx codes are hard to figure out because they have a lot of different causes. If the code comes back after you get a new gas cap it might be worth having a shop do a smoke test on the truck. That would be the better way to pinpoint the problem.

Jimmy

 

On my 03 Dakota the NVLD, (I typed it wrong in the post above) pump is right next to the rear canister. I was getting the P0441 and after trying many things, this was the last thing that fixed it, I found many Internet posts that said this pump is most likely the problem child.

 

On my 2001 the LDP is under the battery tray. I figured a 2002 would be the same. Not all Dakota's have an LDP. According to the service manual the LDP is only on trucks "equipped with certain emissions systems". My truck has the regular 50-state emissons so I don't know which "certain emissions" Dodge is talking about. My truck is a "Low Emissions Vehicle" and also has the "Evap Control Systems" option on its build sheet, so maybe that has something to do with whether a Dakota has an LDP or not.

I had to replace my own LDP after I was in a wreck back in 2010. My CEL came on a few days after I got my truck back from the body shop, the code was P0441. I replaced my gas cap and the light was on again 2 days later with the same code. I repaired a couple of hoses that looked cracked and the light came on again 2 days later with the same code again. So I bought about 6 or 8 feet of emissions/fuel line hose and replaced all of the rubber emissions hoses under the hood and also replaced the two small right-angle hoses at the evap purge solenoid.

I did some research and found that the LDP is in the same area (left front corner) where I had been hit in the wreck. I figured the LDP could possibly have been damaged in the wreck but I had no way to know for sure. A new LDP costs $140.00 at the Dodge dealer here, and I did not want to spend that much and still not fix the problem. So I bought a used LDP for $20.00 at the junk yard, it came from a "Cash For Clunkers" truck. I installed it and replaced the rubber hoses under the hood, cleared the code and have not seen it or any other codes since.

There is a diaphragm inside the LDP that can go bad. The LDP may or may not be bad though, I guess the Dodge dealer could find out with the DRB-3 scan tool and a smoke test. Emissions leaks can be hard to isolate unless the fault is really obvious, like a damaged hose or fuel vapor leak/fuel smell.

Jimmy

 

This is the one that comes off the service port, and goes to the canister, right? Would anyone happen to know the part number, or "formal" name for this hose? My dealer can't seem to understand what I'm looking for.