angel71rs

Getting a PO440, had it before so already checked the EVAP cannister purge valve (clean/functions), new gas cap, replaced a rotted clamp at the cannister, problem went away for ~ 1 year, just returned. So I find this just sort of hanging around by the fuel line:


Another view:


Looks like it is the gas tank vent valve, busted, and it should go in the hole in the brake line bracket hole indicated by the arrow. But the drawing in the manual looks different? Generic drawing maybe?

So is this the gas tank vent valve, anyone have a pic of what a good one looks like? I'm thinking it might be the root cause of the code if it is the vent valve.

2001NBMZ28

Yeah think it's the fuel tank vent. Don't have a pic of mine, does the one in your manual look like this? http://shbox.com/1/fuel_pump_wiring.jpg

angel71rs

Thanks for the link, great pic. Nah, drawing looks different than that too. Looks like my vent valve is busted, missing everything except the outer body. maybe road debris damage???

Anyway, parts stores don't carry it, didn't even know what it was, not on their computer. So went to dealership, they didn't even have it, had to special order, be here next week. Will post a pic for future reference when I get it.

angel71rs

Got the part, 10245442. Wierd thing... googling it says it's for 93-97??? Maybe cause the 98s still have a metal tank. Anyway, had a hell of a time getting the busted one off, had to stick a small screwdriver under the hose to get it off the busted valve. Not a rubber hose, some type of black plastic covering over white plastic inner lining. Goobered it a bit, so put a clamp on it. Gas tank vent valve:



And this is what it looks like installed:



When I crawled under the car to do the work, gas smell was heavy, courtesy of the busted valve. Glad nobody tossed a butt under there before I found the problem.

.

2001NBMZ28

Cool, hopefully it'll make the P0440 go away.

Crimsonnaire

iTrader: (1)

That white plastic thing is the evap vent valve?

With the car lifted, is it visible and out in the open? Is the evap purge canister nearby? Is the canister hard to replace yourself?

Where did you buy the vent valve from? I tried searching for it on eBay, but nothing.

angel71rs

The white bell shaped thing is the gas tank vent valve. It's connected to the top of the gas tank. With the car lifted, it is readily visible on the brake bracket by driver's side wheel.

There is a seperate vent assy for the evap cannister. Rectangular looking thing sitting on a bracket under the front of the gas tank, behind the axle on my 98. I removed it to test the valve with 12volts just out of curiosity to see if it was functioning, as long as I was down there. Here is a pic of it:



Cannister is behind the cover behind the driver's side wheel. I tried to pop it off when I had to replace the rotted clamp, but couldn't. The drawing in my manual makes it look like it clips onto a bracket, but I couldn't figure out how to do it. Had to do the clamp while it was still installed and it sucked. You can remove the surround from the tank filler neck and have a look at it thru there. Just don't use a drop lite with a bulb or you might go boom.

I didn't find any trash in the cannister purge valve (located on intake manifold, driver's side), so didn't think cannister was fubar, just needed a new clamp.

Got the gas tank vent valve at the dealership, had to be special ordered, ~ 25 bucks. Gm parts direct lists it for 13, but they have a rep for raping you on shipping. Search 10245442 here: http://www.gmpartsdirect.com/

That is the pn that came up at the dealership when he entered my VIN, your car may take a different pn.

0440 gone, along with the occasional whiff of gas smell I used to get.

Crimsonnaire

iTrader: (1)

Thank you VERY much for the clarification and the helpful pictures and link.

I've got a P0442/0440 code that I want to get rid of. I've already replaced the gas cap a while ago, so that's elimitated. Now that I know the vent valve is visible from the bottom, I'll inspect it the next time I have the car lifted up. I'm gonna hold off getting a new vent valve until I confirm that my current one is damaged, so I don't risk wasting the $25. At the same time, I want to inspect my purge valve. Do you remove the purge valve by just pulling on it? And do you also have to remove it from a specific end first, or is it detachable at both ends?

Would you happen to know the part number for the canister? I couldn't find any references under a description search on Yahoo! or eBay.

Thanks again.

angel71rs

Purge valve on the intake? You squeeze/push on the clips that retain the front and rear hoses, they pop right off if you do it right, very little force required. I actually disconnected the front one where it connects to the intake cause it was easier to see how the clip had to be worked to release it, then popped it off from the valve once I had it off. Then unclip the electrical, #1 injector wire (don't lose the little gasket inside the connector), and it slides right up from it's mounting bracket. Here is a pic:


Tap it on something light colored to see if any crap falls out of it; that can mean the cannister is falling apart internally allowing crud to get sucked up to the purge valve.

I also tested the valve with 12 volts from a small power supply I have and a lenght of speaker wire with the ends terminated into red butt connectors (perfect for sliding onto connector pins without shorting). You can hear and feel it click; polarity not important.

Don't have PN for cannister, but you can try the "catalog" tab at gmpartsdirect.

Heads up on the gas cap: my research into evap codes lead me to a thread in which some guy said a gas cap he bought at a parts store was defective. Around here inspection stations can test the cap seperately, maybe you can have it checked if you can't find something obvious like my busted tank vent valve.

Crimsonnaire

iTrader: (1)

Yes! You are the MAN! Now I'll be able to replace the purge valve myself if necessary. Thanks so much.

I had the car lifted up yesterday, and I couldn't find the the white vent valve at all! I looked all over, and just saw bunched wires running along the area with nothing clamped onto the bracket where your vent valve is clipped onto. Then, when the technician called the dealership about it, he was told that if the vent valve isn't at the bottom, it'll be located above the gas tank. I figured one of the previous owners might've modded this part. Of course, the other possibility is that it was removed altogether! I took a picture with my phone, and will post it up later if I can figure how to send it with the Chocolate phone (I'm used to the Razr).

I see you drive a 98 Z28. Mine is a 99 TA. Were the vent valves placed differently between the F-bodies of this period?

angel71rs

Vent valve location might have changed since the 98s were the last to use the metal gas tank.

Crimsonnaire

iTrader: (1)

OK. I had another look at this section, and this time, I took high-res pics with my camera.

My car's got the same bracket as yours where the white vent valve is clipped onto, except I don't have a valve OR a line for a valve to connect onto!




Could someone have removed this vent line and valve entirely or relocated them? What purpose--if any--could there be for someone to remove it?

1976CamaroGuy

iTrader: (8)

Anyone know if one of these can be used in a LS1 retrofit to prevent tank pressure build up? This is going in my 1971 camaro BTW

torkls1

iTrader: (15)

I understand this thread is almost five years old, but does anyone know where I can find this fuel tank vent valve?? The part number is 10245442. I looked everywhere online, and every website says part is discontinued. I found one website that said it was still available, i ordered the part, and received an email saying the part is discontinued. I even called dealerships and they don't carry the part anymore.

Is there a new part number for it, or is there some other type of valve readily available I can use instead? I'm a little stumped on this one. Thanks in advance!

chopperb

iTrader: (1)

Gm parts direct has them. About $15

http://www.gmpartsdirect.com

torkls1

iTrader: (15)

Thanks for the quick response, but I just looked it up and it says part is discontinued...

wssix99

iTrader: (5)

That could be just a quick response. If you ask them to do a "nationwide search," you may find it sitting on another dealer's shelf, even though its discontinued. I understand it takes folks an extra step to do this at the dealers vs. checking the central warehouse inventory. We're having this issue more and more now with all sorts of parts.

torkls1

iTrader: (15)

Very good bit of information to know. Makes sense this issue is becoming more prevalent; some of our cars are already 15 years old.

I'll have to make some phone calls to some dealerships tomorrow. Thank you!

torkls1

iTrader: (15)

To follow up:

Called a dealership yesterday, and had them do a nationwide search. The part was unable to be found anywhere nationwide. I've called some junkyards to find the part, and was unsuccessful. Needless to say; I am not having fun finding this damn part.

wssix99

iTrader: (5)

I wonder if this part is a carry over from the LT1 for 98 only. I don't see any mention of it in the Service Manual for my 99.

Anyway - Classic Industries sells a similar part for older cars and its only a plastic housing with a cotton ball stuck in it. If that's the case, I'd totally trust one purchased used from a yard. (The one Classic Industries has is just the housing - the owner has to supply their own cotton ball!)