All,

In your experience with this issue where is the culprit? The Canister or the Valves?

Here is the map from Courtesy Nissan (scroll down Maxima (A33B) 223 Vacuum Piping 2002 3.5L [B 02])
http://www.courtesyparts.com/maxima-...1988_1991.html

I am look at these parts and hoping I don't need all of them.
14920+A Maxima VALVE ASSY-CONTROL
14920+B Maxima VALVE ASSY-CONTROL
Maxima CANISTER ASSY-EVAPORATION

 

check your gas cap before anything else

 

Did you overfill your gas tank? Happened to me once, and after a few cycles it turned off by itself.

 

Same as the above two posts.

 

Changed cap to aftermarket same issue... questioned the new cap changed back to the old one but mived the new rubber o-ring to it,,, same problem.

 

there are 3 options. very small leak, small leak and large or gross leak. Sometimes u could get some other coded like vsv or malfunction. large leak could be a number of things. Most of the times it is a loose gas cap. However sometimes it could be something else like a loose line, cracked canister etc.
You may want to have someone check the gas cap on a tester first, then check for corrosion on filler neck (that's usually small leak) and then he would have to smoke the system if nothing obvious is found.

 

Usually aftermarket gas caps will not seal properly. IMO never use an aftermarket cap.

 

Gas cap seldom emit a "large leak".

You may need to smoke the system.

 

My experience: I used to get gross & small leaks. Bought an aftermarket cap from AutoZone, that didn't fix it & it seemed like the OEM cap made a better seal. The actul culprit was not the gas cap but the actual gas-filler-hole or whatever you call it. It was rusted to heck. So basically check your cap & what it's supposed to mate to. I had started looking into the EVAP cannister replacement too...good thing sandpaper fixed the problem & it hasn't returned since I sanded it (month ago). I probably will have to continually monitor it though.

How mine looked, before I bought some sandpaper and went to work:

 

Did the gas cap from courtesy Nissan, OEM... still getting the code. Sometimes goes away after filling but comes back quickly.

 

My moms titan had that because a hose was loose.

 

Why would sanding the gas filler hole help the code go away? I am having trouble with this issue but also the previous gas cap and the new one I bought does not seem to screw on very tightly since it is easy to open after the clicks.

 

I'm not sure. I still have this problem. Will probably need to have the system smoke checked and see it something is open or cracked.

 

Either sanding had nothing to do with my problem or sanding was a band-aid. I lasted about 2 months with no P0455 or P1448 after sanding, but now those codes have come back. I think I need to do the canister/valve replacement.

 

My light would come and go every few weeks.Ended up cutting off the plastic piece that hooks the cap to the car since it would tangle itself around the cap and loosen it up some.

 

I'm new here but I have exhausted the search functionality trying to make heads or tails of what the piece parts are for this problem.

Anyhow, I have an '02 Maxima SE which I acquired last week. The previous owner mentioned how he had the SES light come on occasionally but just cranked on the gas cap and all was well (the light never came on when I test drove it the first time nor did it come on when I went back a few days later to do another test drive). From what I have read so far on the forum this appears to be a common issue. However, once I had posession of the vehicle, the first time the light came on I had P0456 as the code. I assumed this was related to the whole gas cap issue. I cranked on the gas cap, cleared the code and all was fine for ~2 days. After that, now I am getting P0455 and P1448. I cranked on the gas cap again, cleared the codes but to no avail, they keep coming back.

So I've read that the first fix is to get a new gas cap. I did purchase a new gas cap from a local dealer. Upon looking at the new gas cap, it doesn't look any different than the old one. What is the issue with the gas caps that leads one to replace it? Is there anything physically wrong with it? The rubber grommet/ring looks to be fine on the old one, I took it off and cleaned it up, tried revitalizing it by letting it sit in some oil for a little while, cleaned it off again and put it back on the old gas cap.

I'll try the new gas cap but I'm not convinced that it'll perform any different than the old one until I know what is the failing issue with existing gas caps. I've never heard of failing gas caps or ones that wear out (well, at least not on any of the other vehicles I've owned).

I've looked at the FSM pictures of what the valve and cannister look like but I was wondering if anyone had actual pics of what they look like and where they are exactly located. From what I've read it sounds like an easy replacement but having an actual pic. would be helpful, the FSM drawings confuse me a little.

Also, there was what appeared to be surface pitting on the filler area, very similar to the pic. shown in a few posts above. I tried sanding that down as well.

Any insights would be helpful.

Thanks