Car: 99 Fed spec

Problem: p0440 - due to cracked vacuum cut bypass valve (major leak) and leaking vacuum cut valve (minor leak). (note: CEL only comes on after stopping/idleing after hwy driving, and the cut bypass valve is functioning electronically)

solution: 1) Bypassing both the vacuum cut bypass valve and the vacuum cut valve so the system is either constantly open (by adding a bypass hose [in red on diagram] and therefore always feeding vacuum/vapor into the fuel tank. (I have it setup like this right now. No codes, but I doubt the canister storage system is working at all) Or 2) plugging the right side of where the red bypass hose connects in the diagram, and keeping the system closed altogether.

Question: Considering the vacuum cut valve is generally closed, is it possible to do solution 2, and simply close off the system so manifold pressure is never brought back into the fuel tank? Can anyone see this causing problems to other aspects of the evap system or preventing it from working altogether?

Thanks in advance for anyone who's got a theory on this.

 

If you go through with number 2, then your EVAP system will be disabled.

Is there a reason you haven't considered the obvious, just replacing the two damaged parts?

 

^+1 seriously!

If you don't have to worry about emissions, do whichever you want.

 

Question:
Should the evap canister ever be emptied?

Also, i noticed my 99 SE-L had different EVAP components on top of manifold compared to my 95. Makes me wonder if keeping my EGR with 00vi swap is a good thing since Nissan updated some EVAP/EGR stuff on 99-01 models.

 

I'll change them eventually once I can source some used parts. Right now I'm bypassing as a troubleshooting measure to make sure there are no other leaks and I want to be sure I'm not screwing anything up in the meantime. So if my #2) suggestion of blocking off will cause the evap system to be disabled. Will the #1) suggestion of running a hose that bypasses the 2 valves allow the system to function, or will it pose a problem if vacuum is constantly applied to the fuel tank, allowing fumes to travel to the canister while the car is operating?

 

My 98 Maxima with 137k miles just got error code P1446. The EVAP vent coltrol vlave was stuck closed. After cleaning the solenoid with brake cleaner then appling dielectric grease the solenoid easily closed while applying 12V. While doing this I also removed the canister and the several hoses and components to give it a cleaning. While removing 1 of the 4 hoses attached to the vacuum cut valve (173723S500) I broke 1 of the plastic noses. The dealership wants $115 for this tiny plastic peice and only 1 online parts store is carrying it for the same price. I'll try to glue it but being so tiny I doubt it will hold very long.

I'm going to temporarily insert a hose to bypass the 2 vacuum cut vlaves then head over to junkyard for replacements parts. As the parts salesman at nissan said 'They're asking for way too much for these simple parts.'

 

I got the error code P1446 in my 02 GLE (Evap canister vent control valve-closed). I also have noticed a strange thing that happens when filling the gas tank. When using the latch on the gas nozzle to fill until full, it only allows a couple gallons before it shuts off as if the tank were full. I've done this a few times with the tank on empty so I'm sure it's not full. Are the two problems related? Should I replace the entire evap canister?

 

You should post in you're own generation forum, and not bump a 2 year old thread.