Still can’t add fuel

[Jeffd]

I’ve had my ‘00 Boxster S since October and have never been able to add fuel without it overflowing and shutting off the pump. I replaced the purge valve (under the intake manifold) first as I had a CEL for that. It cleared the CEL but had no effect on the fueling difficulties. I then threw parts at it and replaced the tank bleeder valve which did no good. The one it replaced seemed to work exactly the same when I blew through it and manipulated the lever that’s pressed by the fuel cap.

Anyway, I can fill it to 3/4 tank fine if I disconnect the fitting that connects to the orange side of the fuel fill valve. Once it gets to 3/4 with that hose disconnected it shuts the pump off but that’s how I’ve been operating. I just leave the fender liner off and I disconnect that hose to fill to 3/4. Apparently there’s another vent valve at the top of the tank and I assume that’s the only remaining suspect. Does anyone know how to properly test that prior to throwing more expensive parts at this problem?

[Jeffd]

Oh, I used to also have difficulty starting after adding fuel but that was also resolved by replacing the evap purge valve under the left side of the intake manifold.

[Lowski]

Sounds like something in the Onboard Refueling Vapor Recovery (ORVR) system isn't working properly. You can verify your car has ORVR by looking for option code M664 on the sticker under the frunk lid.

I worked with the system a bit solving my coke bottle noise problem and the occasional hard to fuel problem. There are a lot of threads out there about it. Read this system description and the following thread.

ORVR Valve location: 2000 Boxster?



Checking the fresh air valve (11) in the wheel well can be done by listening for the valve solenoid to click it open. Remove the gas gap, stick you finger in the filler neck and push the flappy thing all the way up. This will trigger the magnetic reed switch (9) and actuate the valve. You should be able to hear it.

You can do the same thing for the ORVR valve (6) on top of the tank, but I had to disconnect the fresh air valve (11) in order to hear it click.

I would also check the hose that connects to the housing that the fresh air valve (11) is in. If this is plugged you won't get the air flow you need.

Of course check your E36 fuse.

[Jeffd]

Thanks, I hadn't seen that particular diagram in my searching. It doesn't help that the names of the parts isn't consistent across all of the sources I've seen. I had the coke bottle sound but replacing the purge valve (tank venting valve in that diagram?) and the tank bleeder valve (Operative venting valve in that diagram?) seems to have resolved that. The purge valve was definitely bad, not sure if the tank bleeder valve was a waste of money and effort or not. The reed switch works and clicks valve 11 and/or 12 in that diagram. I'll have to locate the ORVR valve and see if that's opening with the reed switch or not.