1996 850R - Large fuel leak from front of car, disappeared on its own?

mudchicken · Post by **mudchicken** » 07 Jan 2021, 18:36

Hello all, something odd has happened today. I was sitting at a red light and I started smelling a very strong smell of gas through the vents. My gas light also came on earlier than it should have, I pulled immediately into a gas station and noticed a large amount of gas dripping from the front of the car. It wasn't quite a stream, almost raining. There was a large puddle under the car on the drivers side-ish. I turned the car off and waited around 10 minutes, upon starting the car again the leak seems to have disappeared. I didn't get a good chance to find the location of the leak and now I am unable to, injectors and fuel rail look dry so I don't believe it's that. I am now worried to drive but there definitely doesn't seem to be a leak anywhere now, adding more gas did not reproduce the leak.

Post by **volvolugnut** » 07 Jan 2021, 19:18

Start the car in a safe place with a fire extinguisher on hand. With the engine off, the fuel pressure would quickly drop and the flow would stop. With the engine running look at the fuel rail at the ends and at each injector. Also, look at fuel lines and connections under the hood. You should see the leak under these conditions. Be careful.
volvolugnut

mudchicken · Post by **mudchicken** » 08 Jan 2021, 08:23

volvolugnut wrote: ↑07 Jan 2021, 19:18 Start the car in a safe place with a fire extinguisher on hand. With the engine off, the fuel pressure would quickly drop and the flow would stop. With the engine running look at the fuel rail at the ends and at each injector. Also, look at fuel lines and connections under the hood. You should see the leak under these conditions. Be careful.
volvolugnut

Thanks for the reply, I got my fire extinguisher and with the car running I am not able to detect any leaks at all which is concerning to me, I have taken a video showing everything dry and nothing dripping, not that a video of nothing leaking will help but just proof that I'm not going crazy. There's also no more fuel smell. But just yesterday I was forced to pull over and saw it raining down with my own eyes, after which I drove ~10 miles home stopping every couple of miles to check for leaks.

Post by **volvolugnut** » 08 Jan 2021, 08:46

I believe you. There was a fuel leak, they are dangerous and will not fix themselves.
Perhaps use a fuel pressure gauge to check for abnormal fuel pressure - high or variable. A restriction in the return fuel line may have caused a leak, but it should not no away.

Anyone else out there have ideas.

volvolugnut

Post by **manovlov** » 08 Jan 2021, 15:07

Could it come from the reservoir overflow pipe, after have jumping on a hole in the street ? I had an issue with my fuel filter last yeart. Tried to replace it but it was impossible to disconnect the ff from its hoses. I've ordered new parts, and twice i was fulling the reservoir, there was gasoline out. The guilty one was (by my fault) a hose not correctly hose ring screwed. Are you sure it came from the vents ? Could it have come from the back side ?

With a car this age, i would have the all gasoline hoses diagrams, and replace all of them.

Manov

mudchicken · Post by **mudchicken** » 09 Jan 2021, 14:25

volvolugnut wrote: ↑08 Jan 2021, 08:46 I believe you. There was a fuel leak, they are dangerous and will not fix themselves.
Perhaps use a fuel pressure gauge to check for abnormal fuel pressure - high or variable. A restriction in the return fuel line may have caused a leak, but it should not no away.

Anyone else out there have ideas.

volvolugnut

Using a fuel pressure gauge I have ~43psi before start up, and ~35psi when running idle. I believe that is within the normal range. I took off the vacuum line to the fuel pressure regulator to check for gas and i believe I smell gas in the line. Could gas have been pulled through the line into my charcoal canister? If im not mistaken the canister is in the driver side wheel well correct? The leak left a puddle near that area. I'm getting it up on a lift in a little bit to check it out from underneath.

Post by **jreed** » 10 Jan 2021, 06:50

Yes, the charcoal canister and vent valve are mounted in the driver side wheel well. The vent valve is closer to the driver and the canister is closer to the front of the car. I have heard that it is possible that the charcoal canister can get flooded with liquid gasoline (and not just the vapors it's designed to absorb) if the gas tank is overfilled during refueling.