asylumdown

hey folks, first post to this forum board!

I found my way here because I'm not sure where else to ask/find an answer for this question:

We have a 2007 lexus GS450H. So far it's never done anything unexpected and we have been religious in keeping up with it's maintenance schedule. On Tuesday night we stopped at a Shell station here in Calgary to fill up the tank so I'd have gas for my trip out to a field site for work this morning. My normal practice is to pre-auth 80 bucks worth of gas, select premium, and fill until it's full. It's been a while since I filled up, and gas was WAY more expensive this time than when I last filled up ($1.44/L), so my 80 bucks ran out before the tank was full. This was around 10pm.

This morning at 8am, I went in to the garage and was greeted by the overwhelming, punch-you-in-the-face smell of gasoline. Walked up to the car to discover gas all over the side panel of the car below the gas cap, and a large puddle of it on the floor trickling towards the garage floor drain. The hose at the gas station never clicked off the way it would if the tank was full, the gas cap was tightly affixed, the tank never overflowed at the station, the temperature when I filled up was around 12 degrees C and my garage is held at a constant 18 degrees C.

I've never, ever had this problem before. My garage floor has an epoxy coating and the spilled gasoline has pretty much ruined it wherever it pooled.

Does anyone here have any ideas as to why this might have happened? Is my gas cap FUBAR? Even if there was a problem with my gas cap, is it normal for gasoline to creep up and out of the tank like that? I didn't have a choice but to drive the car 100km away to my field site this morning and the car performed as expected on the highway both going and coming back, and the gas gauge went from right at 'full' to where I'd expect it to be after a 200km round trip. I'm totally stumped. I'm selling my house at the moment so having a massive, permanent brown stain where the gasoline reacted with/sunk in to the epoxy is exactly what I don't need, and I don't want it to happen again and get worse.

bigblack06

iTrader: (20)

I've never heard of that, although it could have been the electronic door that closes and basically spilled the overfilled gas out.

worker

I've never heard of this either. Even with ppl topping off their gas, none of them get overflow like this. Very weird.

TWong350

iTrader: (8)

Wow! I have never heard of such an issue either. Perhaps the nozzle at the gas station is faulty that didn't sense when it was truly full?

Be prepared that you may get a check engine light if your evap canister is soaked with fuel.

morganc

As mentioned before, it's quite possible that your canister is plugged. When you are parked, your tank is completely sealed and some pressure can build (lines bleeding down etc.). When you press your fuel door button, the ECU opens the Fuel Vapour Containment, and this relieves tank pressure.

You could be into either a: fuel tank pressure sensor, fuel vapour containment valve, canister, but I think that it might be a Fuel Cut-Off Valve (this is a part of the Fuel Tank Vent Hose Sub Assembly and/or the Fuel Tank Breather Tube Sub-Assembly). It could be a pain to replicate and fix, but for the time being, keep it to a maximum fill of 2/3 of a tank.

If it hasn't thrown any codes, then you have to start thinking about passive components, rather than electronically controlled ones (because a tank pressure sensor, for example, will usually self-diagnose).