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Thread: 01 IS300 with a p0440 (pic) Reply to Thread
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  Topic Review (Newest First)
04-17-2019 07:35 AM
chappys4life I know I’m bringing back an old thread but going through the process in my 01 IS300 now. I got the old valve and the new unit in. I am struggling to get the bigger hose with plastic connector onto the tube. Anyone run into this and have any tips?
11-08-2017 02:09 PM
greasemonkey2 Just picked up an 02 w 128K. Had p0440 and p0442 codes. smelled gas back of car during warm late afternoon. Glad this post is here. Great info. Went to Junkyard and practiced cutting the hole there. removed the metal chuck and used as template for my car (brought sharpe and marked critical areas on template). drilled single hole w larger bit closest to drivers seat. Used tin snips to cut three sides and peeled it back toward the trunk. I cut more into the hump between the seats so I could access the dredded larger hose (glad I did). Removed small hose. Then removed valve from tank. pulled on it to get to larger clip. Used two small slotted screw drivers (one for each snap on connector). Stuck the drivers into the connector to release both lock features and it pulled right out leaving the drivers in place as I pulled. Took 15 min to remove and reinstall valve once hole was open.

I used some sheet metal and cut a 7"x7" "L" about 2-3" wide. I bolted that on two sides of the new access hole on the underside of the car. Bent the access flap back over and used sheet metal screws to secure it in place. Just used some tar HVAC tacy putty to seal up the edges of the access hole. This extra metal restored the rigidity of the hump area. I figured the tar putty will give upon movement and maintain seal.

Great post!!!

Was a plastics engineer. Looked for weld line or crack in check valve w jewelers glass (what we do to root cause failures in the industry). I couldn't find it. The metal rim on the tank side of the doughnut seal had surface corrosion. I'm thinking mine was leaking at the seal.

No more fuel smell. Only a few hundred miles. Code wouldn't throw until I racked up about 600-800 miles. So I'm in a wait and see mode.
03-08-2017 05:13 PM
ziocam I think getting it back together as well as you can will be good enough. I remember when I was putting everything back together that I bent a tab on one side and I was afraid I had broken it entirely. I shoved the hose as far onto the nipple as I could and at least one side engaged. The other side might have as well, but I kinda doubt it. I don't know what the hose is for specifically, but I did this fix more than three and a half years ago and I haven't had another problem with it since. In fact, I haven't had the CEL come on at all since this issue was fixed.

Maybe someone else has better information about what it is or how secure it needs to be. If not, I wouldn't worry about it at all.
03-08-2017 04:52 PM
Zachj When replacing the fuel tank over fill check valve I got the big hose off with some work but after replacing the valve I went to put the large hose back on I figured it would slip right back on but for the life of me I could not get the teeth back over the F'ng ridge. I ended up breaking one side in the process, the other side is clipped on. So my question.. what is the larger hose exactly? It seems like the hose just seats up against the valve nozzle. Does this need to be a tight seal? The clip on the other side is holding it pretty well, it's not going anywhere. Do I need to worry about it being a tight seal?
I figured if it was supposed to be an air tight seal it would be like the smaller hose that fits tightly into the smaller valve nozzle with the hose clip.
06-05-2015 11:58 AM
Originally Posted by dat2109 View Post

Out of curiosity, who has just epoxied the crack instead of replacing the valve? (they are all cracked in the same place, right on the top edge)
Hopefully no one lol Its just a $35 part including the gasket.
06-05-2015 11:55 AM
dat2109 I had to do this repair too.

The rollover valve hold down plate uses 8mm or phillips head bolts, 6 of them.

Out of curiosity, who has just epoxied the crack instead of replacing the valve? (they are all cracked in the same place, right on the top edge)
03-23-2015 09:32 AM
RobertDIY Thanks for all of the help. I did this repair yesterday and made a video.
01-24-2015 04:59 PM
mm71522 I drilled small holes all the way around using a small spade drill bit..careful, only put the tip in
I was afraid of hitting something underneath, so I got a flathead and hit it horizontally. It would slightly break in between the holes easily. I wanted there to be metal to metal contact when sealing it. Putting it back together was a bit challenging bc it was such a tight fit, and it had to be perfectly leveled. I sealed it with marine JB weld. If anyone does this, you can also vacuum the dirt around the valve before you remove it. You'll be thankful you did.

I was on a short deadline to do my smog. I wasn't able to pass by resetting the ecu. The ecu monitor on the scanner wasn't ready, and by the time it was ready my CEL was back.

The crack on the valve, it had another smaller one on the other side.

No creaks, no gas fumes in the cabin, and no CEL
01-24-2015 02:29 PM
mm71522 I'm with you. Your pics helped, exactly what I did too and it got rid of my P0440. I've driven about 700 miles since and everything good. I opened it slightly different but it works! I'll post pics shortly.
01-24-2015 02:13 PM
darkknightrider Ok guys I can confirm that this short cut does work, as long as you make sure to seal any gaps when you put the metal back together. I used dynamat to create an air tight seal and looks like nothing was ever cut . Now as far as the big hose goes there are two little teeth that need to pushed away from the hose for it come out. Was a little tricky at first but dont worry youll get it. Putting it back in requires the teeth to grab the valve again, not too difficult.

Only warning is when cutting make sure you dont cut too deep towards the rear of the car, there is a black fuel line. BE VERY CAREFUL. I only used a power tool to make the first hole towards the front of the car. After that I used a metal cutter that was strong enough. Then I bent the metal away from the valve. Overall i am stasfied, the smell of fuel is gone, and the codes (P0440, P0446) have not come back. I packed the dynamat in nicely, so it looks like nothing was ever done.

Dont be intimidated by cutting, save yourself some money, as long as you know what your doing and follow this thread you will be OK.
11-12-2013 06:06 PM
mm71522 Thanks for the pics! ^ Finally my CEL will be gone :-)
11-12-2013 05:48 PM
Is there a way to disconnect the connector that is connected to the check valve? I know you have to pinch somewhere to disconnect it but I don't know where to pinch. Where do I pinch. Can you recommend a specific tool?
Ya, this was the hardest part of actually changing the valve. Of the two hoses, one was very easy to disconnect. I did that one first. Then I actually pulled the valve off the tank and twisted it so I could see the fatter hose connection and clips. If you look at your replacement valve, the fatter connection has a rib around it. The connector hose will be inserted up to that line, and 2 clips grab the rib to hold it in place.

In order to separate the valve from the hose, I put on gloves to protect my hands from the sharp metal, used two very small flat head screwdrivers inserted along the protruding hose connector on the valve, toward the tube, to the point that they touched the rib, releasing the clips. This didn't do much, so I crammed one in on top and another on bottom at the same time to release both clips, then I held the hose with one hand and the valve with the other and twisted it back and forth while pulling. I really had to give it some muscle, but it did come free and eventually popped off.

I then removed the screwdrivers, and inserted the new valve into the hose, applying pressure and again twisting back and forth. This is a very tight connection, so I just worked it until the hose hit the rib on the tube. Once it was there, I twisted it around and made sure it would mount back on the tank properly, then I re-attached the smaller hose and inserted the screws to mount the valve.

I recall looking at the hose while it was off and thinking that while it looks like it's a "pinch here to release the tabs" type connection, it's really not. I don't think there is a way you can pinch it to release those tabs. I got pretty rough with mine with the screwdrivers, and that didn't cause any problems, so that's what I recommend you do as well.

Good luck to you! (Oh, and take pictures to help whoever tries this next.)
11-12-2013 05:27 PM
GreenMachine Very good instructions for the changing of the fuel tank overfill check valve. Nice job, thank you. I have been trying this myself but have gotten stuck. I managed to get the hole cut and reached the check valve but I could not disconnect the big connector hose. Is there a way to disconnect the connector that is connected to the check valve? I know you have to pinch somewhere to disconnect it but I don't know where to pinch. Where do I pinch. Can you recommend a specific tool? I just don't want to damage the connector. Any suggestions you can give me would be greatly appreciated. Thank you.
11-07-2013 03:55 PM
Thanks for all the posts - saved me $$$

Thanks to everyone who has posted about this problem. I got the P0440 code a few years ago and have been limping along with the whole reset a day before my emissions test. That worked great until my charcoal canister went out. I just replaced the canister and have been annoyed with this long enough that I decided to do something about it.

I had a trusted dealer replace the canister with a used one I pickup up on Ebay. That worked great - I replaced the gas cap and the mechanic also smoked the whole system and verified that I had no other problems, so the CEL must be the overfill check valve.

I didn't want to pay to drop the tank, so I bit the bullet and decided to cut a hole under the seat. Instead of a sawzall, I went for some pneumatic metal shears. I bought some for $40 - it was easy and safe. I'd do it again in a heart beat.

Here are some pics that may help someone else tackle this problem:

Back seat removed.

I guessed on where to drill the first hole.

I drilled a second hole right next to it, then used the shears to cut the metal. It was like a hot knife through butter. Literally took 3 seconds, no sparks, little penetration, no resistance.

As you can see, the location was perfect! Thanks for the diagram!

Some notes: in order to get to one of the screws, I drilled another hole that I stuck the screw driver through instead of cutting another flap. That worked perfectly. You'll know what I mean if you try this yourself.

Finally, in order to close this back up, I used JB Weld which turned out very strong and holds it very well. While it's not necessary and there may be other ways to seal it easily, if I were doing this again I would get some aluminum tape and a screw. I would put the tape inside the hole before closing the flap, poke a hole in the tape with a screw to hold the tape strong to the flap as I close it, then apply the JB Weld to the crack over the tape. This would give a nice clean seal. Either way, as is my seal was so strong, it is as strong as it was before the surgery, and it may be stronger.

I could visibly see the crack in my original valve, so I know this needed to be done. It's been a week and a half with no CEL, so I'm confident it's all fixed up.

This repair took me about an hour and a half of actual work time because I tried several things that didn't work to re-seal the flap. If I were doing it again with the instructions above, I could do the whole thing in less than an hour, easy. Plan on 15 minutes after you apply the JB Weld for it to set, but it won't be hard for 12 hours or so. I started driving shorty after I applied it and it was fine. I dropped my back seat in the next day after it was as hard as steel.

In the end, I got the whole thing done in a few hours, for less than $100 out of pocket (including buying the parts and the metal shears). I'd do it again in a heartbeat if I needed to.

Thanks again for all the posts about this.
06-27-2013 02:45 PM
503ISthree oh god, I just got this code and same exact symptoms... well looks like I will have to do this fix... good thing I don't got smog till jan. Funny thing is this happened right after I filled up my gas tank at shell... and after 30 miles... LOL!!

P.S. Thanks to all who posted the info, symptoms, and fixes.
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