98 Pathy EVAP system

[andruet]

My 98 Pathy (165K+ miles) has been having EVAP system problems since new (I'm the only owner).

Usually shows up as a an OBD code related to the EVAP canister valves or an EVAP pressure problem.

Canister, valves replaced a couple of times, also had the lines blown out. Lot's of carbon found there.

Everything's fine for a few months then, another Check Engine Light, and we start all over again. I'm on round 4 or 5 now.

 

I know about the filler tube rust-out recall, that's been taken care of. Gas cap is OK.

 

Anyone know anything about this , or similar problems with 2nd generation Pathfinders ?

 

Thanks, folks !

[02silverpathy]

Well, if you have done all of that stuff and still have probelms, I would suspect electrical....what is the condition of the plugs on all of the evap stuff?

[andruet]

Thanks, but everything electrical has been checked, too, including the connections at all the EVAP sensors, etc.

The dealer told me some time ago that this can be caused by overfilling the gas tank. Any overflow "poisons" the canister and can even carry charcoal through the lines and solenoid valves.

But, I DON'T OVERFILL the TANK !

I guess what I'm looking for is some discussion on design flaws, and the like. Is the EVAP canister location a poor choice ? Down low in the rear wheel area places it near the level of fuel in the tank where sloshing could lead to spillage into the canister area.

 

I'm perfectly capable of cheating the ODB inputs. But I have an emissions test coming up soon and this isn't the time to fool around with that.

Is there anyone, with more expertise than this old GM gearhead, like a Nissan-trained mechanic, that could give me more to go on ?

 

Or am I the ONLY one with this problem ?

 

 

My 98 Pathy (165K+ miles) has been having EVAP system problems since new (I'm the only owner).

Usually shows up as a an OBD code related to the EVAP canister valves or an EVAP pressure problem.

Canister, valves replaced a couple of times, also had the lines blown out. Lot's of carbon found there.

Everything's fine for a few months then, another Check Engine Light, and we start all over again. I'm on round 4 or 5 now.

 

I know about the filler tube rust-out recall, that's been taken care of. Gas cap is OK.

 

Anyone know anything about this , or similar problems with 2nd generation Pathfinders ?

 

Thanks, folks !

[GhostPath]

The exact error codes that you are getting would be nice.

[DJ Dank]

I had issues with my Evap system and SES light coming up all the time. After a year of dealing with it turning on and off, I finally found the culprit being the valve in the charcoal box thats lifts and shuts to vent the vapor out of the tank. It was rusted open causing my to throw the codes and causing a small continuous vapor leak.

 

The design is kind of flawed with its location. Too many water/muddy crossings is what I believe the problem was. The 97's had EVAP canister mounted much higher up under the hood which would eliminate that problem IMO.

[XPLORx4]

The 97's had EVAP canister mounted much higher up under the hood which would eliminate that problem IMO.

 

Only the 96's had the underhood EVAP canister. 97's and up have it under the rear bumper.