hey, all!

our i30 has been having a dreaded p0446 (evap vent control valve) code and a small leak code (which happens because of the 0446 one, i assume).
So far I have replaced the vent valve and the charcoal canister (thanks to DCP). Also got a diferent gas cap.
I am thinking it's the connecting harness.
How should i go about testing it? I'm a complete newb to all things electric
Thank you, all!

 

test it using a mulitmeter per FSM

 

tested it per FSM and the voltage with the key on was jumpy, never reached 12v (not even close). was 1-2v at the most. I guess, this is the culprit. Any tips before i take it to the shop? thank you, all!

p.s. also, does anyone know what the resistance of the valve terminals should read? mine's reading at around 10.6-11 ohms.

 

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The FSM says that resistance should be around 30 ohms. I wouldn't let your low reading worry you just yet though. Another test they suggest is putting 12V to the terminals and listen for it to click which normally means there's movement within and therefore, should be functional.
If the terminals of the valve are corroded you will have to scrape through it with your meter probes to get an accurate reading. Also, of course, your meters' battery needs to be in good shape as well.
Whenever I come across a part like this that I have commited to replacing, I always try taking it apart first and often I find the problem to be very simple a little corrosion or dirt or even just a lack of lube. I fixed mine that way when I got that code within a week of buying the car.

 

^^ true. i think the valve itself is fine (got a used one from a member on here and doing the same thing). I'll update as soon as the harness is fixed.

 

1999 ford escort zx2?????

EDIT:

I drove one before...a 5spd. It was a POS but i sure had fun beat the hell outta the gears. lol

 

yup, that's my baby lol i30 is wife's car. the trans' on zx2's are crap (differentials, shift forks, etc). i'm surprised you didn't break it lol

 

that resistance reading that jdooley suggested is for a canister purge valve (under the hood), not vent valve. they might still be similar, however. i will try the 12v to the terminals, but as it stands right now, i'm suspecting a short in that circuit.

p.s. the fuse(10a #17) in the j/b underneath the wheel is good as well.

 

Apparently it's the Canister Purge VOLUME Control Valve, my bad.

 

o we were tryin to lol

Ford may be ****ty but, i respect their Manual transmissions.

 

^^i didn't say ford was lol the trannys' are

guys, can't get the car to my mechanic until next week. What would cause the voltage to be so low there? i've seen the wiring diagram and most of the evap sensors draw their power from the main line (pressure sensor, etc). i assume, the rest of them work properly and get enough power. That would mean that the problem is in that pigtail for the evap vent valve then? what things can i check for myself?
thank you!

 

When you measured the voltage what did you use for ground? Ie, you connected one lead of the voltmeter to the 12V pin, where did you put the other lead? I'm guessing that you didn't find a clean ground if you didn't get 12V.

 

i connected it to the rear crossmember. it was a lil rusty. i will recheck with a different ground after work today.

 

I had to replace the pigtail a couple of years ago because the wire that goes to the ecu had frayed and disintegrated right at the plastic connector. IIRC, one telltale sign that the wire was broken was that the check engine light would come on almost immediately after starting the car twice in succession.
That is, if you clear the code, turn the engine over, let it run a few seconds, kill it, then turn it over again, the light would come on once more. I guess it's a 2 trip thing.

Anyhow, the pigtail is short, like 6 or 8 inches, so giving it a good once over shouldn't be too tough. Beyond that the only thing left to check is continuity from pin 2 of the connector and the ecu, assuming the 12V thing works out.

 

ok. it's def something with the wiring. it does get 12.26v, but when i twist the pigtail the voltage goes nuts. the old valve that i have actually works with the 12v applied to it.
any tips?

 

I'd concentrate on where the wires enter the connector and make sure there isn't any fraying or corrosion.

Realistically, if there is a failure in wiring, then it will probably be in this area because it's the most exposed section. If the pigtail is in good shape then you'll have to start following the wires upstream.

 

just to update the situation: it was the vent valve. got a different one from a jy and no codes since. i guess, i must've been doing something wrong when testing the harness.
on the other hand though, when i take the gas cap off i can hear the fumes escape pretty much each time we have to fill it up. is that normal on the maxima/infiniti?

 

Where did you get a pigtail for this? Nissan dealership told me they did not make have one and the junkyard's have not helped either as they cut all their's when removing the evap cannister. I have a corroded wire that keeps falling out causing the CEL light to stay on.