Hey guys.

I'm supposed to have my emissions tested before the end of January... that's obviously not going to happen, but, maybe you guys can help me get this thing fixed a little faster.

I had a P1336 code, turned out to be a bad ground.
Then I got P0150, changed the O2 sensor and all is well.
Now I have P0440 and P0446, both EVAP system codes.

Am I going to replace the valve on the canister and another code will come up? Has anyone ever had this issue? I'll literally scan it, delete the one code that's in there for what I fixed, and the next time I drive it the CEL comes on again for something else.

The car (96 SE 5-Speed) runs very well. What usually ends up failing on these cars in the EVAP system?

 

UPDATE: Just went to take the canister purge valve off to see if it was stuck/ if I was getting 12V at the harness. I've got 12V, but the heads of both screws holding it to the canister came off when I tried to take it off. Then, I tried to pry off the valve since the heads of the screws weren't there to hold it on, and broke the damn thing. So, looks like I need a new canister and valve, whether they were bad or not.

 

The fact that the same codes don't pop up again is a good sign. Judging by your join date and the fact that you are putting a good effort into fixing the car all of a sudden says that you just bought this car and you bought it with a CEL light on. What usually happens is when a car's CEL isn't addressed right away is it's really easy for other problems to show up without it coming to your attention. The reason for this is that a lot of codes rely on certain parameters to be met before it can actually set a code. So because of the bad ground, it caused the ECU to ignore normal diagnostic tests until that problem was fixed. And so once you fixed that ground, it satisfied the parameter to run the test for less major issues and that's when your O2 sensor test failed and set your next light. You then fixed your O2 sensor and then it was able to test even more extensively and the parameters for the EVAP system to run IT's test was met. This not a bad thing. Soon you'll run out of problems to fix and to be honest... I think this one is your last one considering that no system really relies on the EVAP system. After Googling your codes I wouldn't be surprised if that vent control solenoid was your issue. That'll more than likely fix one of the codes if not both. If it only clears one code you may have to take it to a shop to do a smoke test on the EVAP system considering you may have a vacuum leak in your EVAP hoses somewhere. If you don't have a leak then you may have to change your Purge Control Solenoid on top of the engine. I'll bet though that both lights will go out after changing the vent control solenoid.

 

When I first bought my max I had 6 codes to fix, it took a while but once I got them addressed I have no SES for a while now 8 months (knock on wood)

 

Just replaced the canister and purge valve (since I broke them) and the codes came back after clearing them.

Is it actually possible that there is a leak somewhere? I hate the EVAP system with a passion. Any help anyone can give would be greatly appreciated.

 

The gas cap might be the culprit if you are still getting the code.

 

Also you might have to buy an extension on your tags because when you clear the codes and go to retest, certain systems will read not ready. Then you got to do all that crazy driving stuff to get them ready so just be prepared in case you didn't know that.

 

which codes came back? 446 one or 440 one?

446 is most definitely the vent valve on the canister. 440 is the sub-code of the 446 one. when you said new, did you mean a used part from a member or a brand-new part from the store? had the 446 code on wife's car for a while. after 2-3 different vent valves it was gone.
check your canister to see if any of the charcoal is falling out of it when you shake it (remove the vent valve).
i also suggest you download the fsm: http://www.nicoclub.com/FSM/maxima/
it has the section for troubleshooting codes.

 

I replaced the valve with a new one from rockauto. I know about readiness (for testing).

The gas cap wouldn't cause both codes, pretty sure. Both recurred.

Is there supposed to be a gasket on the valve? The new one didn't come with anything

 

Replace the gas cap anyway. It's not exactly a major expensive part and is easy to replace.

Your original gas cap is probably over 15 years old and it might actually be the problem not being able to hold pressure for the feul tank.

I guess a good test might be to listen to the gas cap when you open it to fill up. You should hear a whoosh sound. This test is not conclusive because sometimes you don't hear that whoosh and the gas cap would still be OK.

You can definitely hear the whoosh sound if the last time you opened the gas cap was when you completey filled the tank, and now its practically empty.


Doesn't hurt.


DW

 

I had the same two codes - P0440 and P0446. Look for a broken nipple on one of the small valves, sensors, etc mounted on the bracket just forward of the cannister. I had one broken - the vacuum tubing held it in place so it looked OK, but when I started pushing and poking the tube would move to the side. I ended up buying the whole bracket with all the various pieces plus a cannister at Pull-A-Part for $32; it fixed my problem and has not recurred in over a year.

 

Gas cap whooshes every time.

I'll check out the rest of the lines... Anybody know if there's supposed to be a gasket between the canister and the purge valve?

 

did you download the fsm? it will answer all your questions and will guide you thru different troubleshooting steps.
depending on the year, your the valve might have an o-ring (if it doesn't go thru the canister when you mount it), if it's the newer type, there won't be any gaskets. from your description, it sounds like you have the newer type.

grab a multi-meter and with key in the "on" position, see if you're getting about 12.5v at the connector for the valve. test the new valve as well by applying 12v to the terminals, you should hear it click.

 

The new one clicks when I apply 12V to it. Also, it sounds to me like I have the old type of valve/canister. The surface of the canister and valve are both smooth, but the valve didn't come with an O-Ring or anything. If that's the case, I guess the leak is between the canister and the valve.

 

does it look exactly as the old one? if so, does the old have the o-ring?
i think i've used some rtv on my old vent valve and sealed up that space.

 

Went to the dealership today and picked up the O-Ring that was not included with the purge valve. Everything seems well now. It appears the purge valve was the original problem.

 

Correction: The EVAP codes are now gone. However, I've driven upwards of 200 miles after a code reset, and the Catalyst readiness monitor is still reading incomplete. What gives? I've followed the drive pattern to a T.

 

drive some more

 

 

Update: The catalyst is still not ready after 800+ miles... I re-read the Illinois Emissions website regarding readiness monitors.

You fail if you have more than 2 non-consecutive monitors that are not ready. So, in short, I could have taken and passed the emissions test before I started this thread. Apologies for this exercise in futility.

But seriously? 800+ miles and still not ready? Now on to fixing the flashing airbag light. Comes back every time I reset it.

 

if all else fails on that airbag light, you might just need the module. it's easily accessible once the center console is removed. 2 screws hold it on each side behind the driver's and pass. seats. get one from a jy or off ebay for cheap.

 

what else could it be? I was thinking I would just replace the module, but how do I know the one I replace it with isn't bad too?

 

if the car wasn't in a collision, chances are it's ok.