I have a 01 Infiniti QX4 and really need to get this problem solved. About every week I keep on getting the P1441 code.. I already replaced the bypass vacuum valve and the control unit to that. I just recently noticed that when i remove the gas cap there's no gases escaping, no hissing noise. So I replaced the gas cap and still nothing.. it seems like theres no pressure when removing the gas cap. ANY HELP PLEASE NEED TO PASS EMISSIONS TEST.. Thanks

P1441 Vacuum Cut Valve Bypass Valve

Look in the service manual to see how to fix it: Nicoclub.com/FSM

I already changed the bypass valve which is the little white vavle with four tubes coming out. I also changed the sensor that attaches to that vavle. What else could it be......

I also had a P1441. I have a 2001 Pathfinder. I replaced the fuel cap with a new one. I pulled and cleaned all the rubber hoses from the EVAP service port to the intake manifold. I pulled and cleaned all the rubber hoses connected to the EVAP canister. I discovered the 2 large hoses were disconnected from the water separator. With a 12 volt battery, I tested the EVAP canister purge volume control solenoid valve, and the vacuum cut valve bypass valve for operation (they were clicking). Using an air mattress air pump, I connected it to the end of the vacuum hose nearest the EVAP service port and pumped air into it while the EVAP canister purge volume control solenoid valve hose was disconnected.

I followed the steps here: http://www.nicoclub.com/FSM/pathfinder/ ... der/ec.pdf

I reset the code and drove it around a couple of times until all tests were complete. P1441 is now gone, check engine light gone, and all I have is a nice green light on my code reader.

That canister at least with my 1997 Q can get real dirty and if the mounting steel work is rusted the canister itself can bounce. The hoses may come out of their orifices and I suspect that if your gas tank has no pressure. Also check your gas cap and hear the clicks when putting it in place.

You will need a bright light to see, no matches or open lights.

I'm trying to fix this problem and the link in this post gets a 404 error for me. Can anyone direct me to the right section?

mbernardo wrote:I also had a P1441. I have a 2001 Pathfinder. I replaced the fuel cap with a new one. I pulled and cleaned all the rubber hoses from the EVAP service port to the intake manifold. I pulled and cleaned all the rubber hoses connected to the EVAP canister. I discovered the 2 large hoses were disconnected from the water separator. With a 12 volt battery, I tested the EVAP canister purge volume control solenoid valve, and the vacuum cut valve bypass valve for operation (they were clicking). Using an air mattress air pump, I connected it to the end of the vacuum hose nearest the EVAP service port and pumped air into it while the EVAP canister purge volume control solenoid valve hose was disconnected.

I followed the steps here: http://www.nicoclub.com/FSM/pathfinder/ ... der/ec.pdf

I reset the code and drove it around a couple of times until all tests were complete. P1441 is now gone, check engine light gone, and all I have is a nice green light on my code reader.

This link should work: http://www.nicoclub.com/FSM/Pathfinder/ ... der/ec.pdf

Thanks Towncivillian- it's a little clearer now.

I have a 98 Pathfinder and this is what I did to fix...First, my code was a P1444 and it also deals with a problem in the EVAP system. I pulled the Purge Volume Control Valve off and blew into an open port to see if it was stuck open. If you can blow through it freely then it is plugged and stuck open, if you can NOT blow through it then it is okay.
Mine was plugged, so i tapped it with my wrench do dislodge the tiny charcoal piece that made it stick open, after that i put it back on. I then installed a clear plastic fuel filter into the line near the Purge Port. (by the brake Master Cylinder, it has a cap on it)
By doing that it will catch any more charcoal from reaching the Purge Volume Control Valve and throwing a code.

What happened is my charcoal canister is failing and coming apart and I didn't want to spend the money to replace it. Hope this helps and will take a picture of the fuel filter in the line so you get an idea of what i did.

Tech notes:
The fuel tank filler cap and the Purge Volume Control Valve are the more common problems that will trigger the P1441 code on Nissan vehicles.

Read more: http://engine-codes.com/p1441_nissan.html#ixzz2zS5cNkSH

http://leo1998.imgur.com

Pics of fuel filter in EVAP line bypassing charcoal canister. Left the canister alone and just installed fuel filter.

I've got the p1441 code - have blown out the lines and checked purge valve, working. installed the little filter as precaution and it stays clean so I don't think I have an issue with canister leaking and plugging up the works.

I've looked at the ec manual, where are you guys finding this particular code mentioned? It's not list in toc and search also comes up empty, am I blind? confused as i read people talking about p1441 as the by-pass valve (checked good) and also the cut-valve, as well as a small leak (and possibly even gas cap - I hear vacuum/hissiung when opening cap so sounds like its good)??

this is a real pita - wish we could test components via the obd interface and pc (act like the consult tools that the tech have).

and of course everything is well rusted underneath at the back so I'm sure the bolts will all snap, if I can even get a socket on to turn them - then additional problem of how to secure the whole thing again.

thanks

well I pulled it all out, only snapped one bolt on the canister bracket so all-in-all it actually came out fairly well - everything seems to check out ok there.
pulled check valve bracket out and it too came out easy considering it's location - thank you bolts. couple of things here:
1. the check valve, only held vacuum from canister side (port a), fsm says it should also hold vacuum on tank side (port b) -so I guess this is my problem and I should replace and hopefully all's well.
2. I also noticed with the cut-valve bypass switch in testing that I could get valve to not open with a bit of sucking pressure - just using my mouth to create a bit of vacuum, not apply super suction or anything. don't know if I'm applying too much vacuum and overcoming it's ability?

also, I went to the wreckers and grabbed a complete system off of another pathy a few weeks back and the check valve tests exactly the same - I know, it can be bad too. would have been nice if it tested like the manual states. guess I'll need to go the dealership for a new one. since there's no electrics on it, maybe it'll be fairly reasonable..

and positive (or negavite) confirmation would be appreciated.\

thanks
Jaime

I went to the dealership to get the cut-valve and it tested the same way , it would only hold vacuum on the one port while it would blow throw with some resistance the other way - so I didn't buy it.

I got back underneath yesterday and disconnected all the plumbing, used a hose to blow into the box while plugging the other openings with my fingers and I could hear air escaping. removed it and used some liquid soap around it to find that air was coming out behind the flange on the vent control valve. I removed it (snaping one of the bolts). there's an O-ring that is supposed to seal it off where it goes into the box. it was still intact but didn't look quite right (little bit of a flat spot). I could also see a crack leading into the opening. Not sure if I caused this trying to remove the valve because of the torque I put on it trying to get the valve off. replaced it with the unit from the wreckers. drove for a while but the code didn't clear so decided to clear it and test drive again so atleast I would know if it happened again. read obd ready states and finally the evap tests read completed and no dash light. so hope to drive it some more this morning and get the o2 ready which was the only supported test not completed. hope it's good and off to get the emission test done as I'm overdue. couldn't believe the number of cops I was passing by yesterday doing my drive.

hope this additional info might help someone down the same road.

well mil light is still off and I've done 600km in the last 4 days, so that's good but the 02 sensor readiness monitor still says that it's not completed test yet so I can't get it tested. what gives, what a pita