First off, let me start by saying this forums rocks! Just purchased an 02 Maxima GLE about four months ago with 146k miles. Was real clean inside and out, only a minor dent in the hood and no rips in interior. Has a few mechanical things like passenger side half shaft is grinding and rack and pinion has a small leak. But this forums has helped me change both the radiator cooling fan assembly (if your wondering 1 hour in Arizona heat wasn't long enough for the coolant to cool down) as well as the spark plugs and PCV valve.


Alright on to why I'm posting. Ever since my spark plug change about a week ago I've been getting all kinds of codes. Five to be exact. P0011, P0021, P0221, P0223, and P1448. I resolved the first four, human error, by realizing that two of the sensors were not plugged in all the way. But P1448 I cant seem to fix. All the hoses and sensors seem to be plugged back in, and I clear the code but it just comes back about 50 miles later. When I originally took the hose with the green twist **** on it (not looking at the car so I cant remember what the little flap on it says) but it was the service port for the evap, you could hear the pressure come out of it. I have taken it off since and no pressure comes out now.

Just trying to see if that could be the issue? I really dont want to have to replace anything with the EVAP canister or valve if it isn't needed.

 

P1448 is the EVAP canister vent control valve that is bolted on to the EVAP canister. It is operated by the ECU, not directly by a sensor on the engine.

It is possible that you are the victim of unfortunate co-incidental timing. These valves do fail on cars in the salted road snowbelt areas. What happens is the plunger in the valve sticks and does not move. You can take the valve off of the canister (2 bolts) and connect 12 volts to the contacts and see if you hear it click. If not, then try freeing the plunger with WD40 (or similar). It may or may not work.

Read the service manual, page EC-568 - 569, link below.
http://boredmder.com/FSMs/Nissan/Maxima/2003/EC.pdf

If the valve itself is good, then start reading the manual at page 564.

 

Good advice, just be careful- those 2 bolts broke off on me, then I proceeded to break off 3 holding the canister to the bracket behind and then- another 3 holding the bracket to the body. All of them were m6, soaked in PB Bluster for days, etc- nothing worked. They simply lost their strength and broke off under torque much less than required to break the rust. YMMV. I had to drill them out, clean the threads, etc- major PITA. The WD40 trick worked for me, BTW. The bolts holding valve created cracks in the canister due to rust but I managed to repair it using epoxy and it is holding fine 6 months later.

 

Alright I will definitely have to try that! Buying a $4 can of WD40/Pblaster is a better start to trying and foxing the problem over a $70 +tax part.

 

Alright, well I got it off yesterday, was fairly easy. Read that I'd have to lift the back end up and such, but didn't even have to. Anyways, when I took it off I sprayed some WD40 in there, and shook it around and you could hear something sliding in there, so maybe it was stuck open. I guess I will find out if the light comes back on at some point.

 

It's probably too late to mention this, but you should have tried to blow air through the valve, both energized and not energized. It should only let you blow air through in one of the 2 conditions.

 

When I was just holding it in my hand you could see right through one hole and out the other, albeit you had to look at an angle.

 

Just a follow up, driven about 300 miles, and the code hasn't reappeared so I'm assuming it was stuck in the open position and the WD40 fixed it.

 

Happy endings always make me cry...