Where do I even start looking? I've checked the obvious, even got a new gas cap just in case. I went to Auto Zone because the check engine light was on and it came back with both codes. They cleared the codes, adn for 2 weeks, the light never came back on. When it did, I was idling in the hot sunshine on the highway waiting in construction. I "felt" something happen, but it's hard to describe what. The check engine light came back on, I managed to turn around, and the van was running slightly rough. Got to AZ again, same codes. They cleared it, adn it's been 2 weeks now, and no further problems. I've checked everything I know to check! Any ideas?

 

Look under the center of the vehicle there are some hoses that attach two black plastic boxes and come piping/hoses. On my 2001 there were some plastic hose connectors that broke off and you could very easily pull the hoses from the black boxes (one is a a charcoal cannister i think) I used some small metal hose clamps to replace the broken ones and that seemed to do the trick.

 

same thing has just happened to me, where abouts are these boxes passenger or driver side frame rails?

 

That is the EVAP system.
The computer system runs tests on it at certain times. If during one of these tests there is a leak detected it will trip the light.
The system has the ability to recognize a small, medium, or large leak.

These can be very fustrating. The small and medium leaks can be very difficult to find and fix. We have sent many out the door with no repair done. Yesterday we had an 01 Ram with a cracked hose on the vapor cannister along the frame rail.

One thing to note, is that this is strictly an emissions thing, and should have no direct effect on driveability/performance.
So your rough running condition, I would say is unrelated.

 

Well, it really hasn't done it again. I should mention that it doesn't run "rough" per se, but I notice the difference. I believe I isolated the problems, even though I've had no codes again. Under the driver side sliding door there is a plasticy pipe (can't see it, I can only feel it) that has a connector. I can easily pull one end of the tube out of the connector. Also, I filled the fuel tank the other day, and gasoline started spilling out under the van when it was almost full. It seems to be coming from the filler hose.

 

Ummmm
your gonna wanna fix that. lol
But that would certainly trip your MIL.

 

the boxes are in the middle of the car one under the firewall area the other a foot or so back. I got to them from the drivers side under the driver door without jacking it up

 

I'm having the same issue. My light tripped and AZ (after running scan) was a small Evap leak. Talking to my father who is a mechanic agreed and said they are tough to find. Most times can only be found using a "smoke machine" to detect where the leak is coming from. Mine is still under warrenty is heading there next week to be fixed. Or should I say "yup all fixed" but just by clearing the codes hehe.

 

even with our smoke machine the small leaks are a P.I.T.A. to find

 

Do any of you dealer guys have a part number for the hose on the vapor canister the goes from the top to the side and is about 3/4 to 1 inch around. While on the subject does any one know where to get a list on the part #'s for our trucks soI have them. I am sick of going to the dealer for a part and being told we need the part #. My inlaws own a trans shop and they ask me the same thing. Such a pain to have to explain it just to get a part.