Gas Leak at engine bay after Car sitting for a while

[archny]

The car is a 1993 300zx convertible on stick with no mods to mechanics. Stock original engine and engine bay. The issue with the car is very weird and two mechanics cannot figure out why. This happend several times. After the car is sitting for a while when I turn on the car on (and this only happens sometimes not all the time) the car start dumping fuel. Its not droplets but more like if you cut a line and let it go. When I look underneath the car the location of where the fuel is spilling is in the back part of the engine bay next to the transmission. The leak is not from the top of the engine from what I can see and everytime this happend the car was by my house and I couldn't lift it to see the exact location of the leak and I won't drive it to the mechanica while this is going on. The weird part is I will turn on the car the next day and nothing is leaking at all. I will drive the car for a week straight and no leak. Then again out of no where when there is a nice day I want to take it out and again it starts all over. The mechanics of course are telling me they can't see anything wrong. We changed some fuel line hoses that started to dry out thinking that might be one of the problems but that didn't solve it. I have owned the car for a while and this was never an issue until a couple of months ago. Any body ever experience this.

[NolimitZ32]

When the car is driven (when not leaking) does it drive normal? For that matter does it idle normal when the leak appears?

[archny]

Yep. It runs normal in both scenarios. The leaking fuel does not seem to affect the idle. You just get a strong gas smell coming into the car.

[NolimitZ32]

That is wierd, have you checked the fuel damper and regulator for leaks? Thats the only place towaards the back of the engine that the fuel runs other than the fuel rails.

[archny]

I didn't check those myself but I will check those. What is weird is if they leak they should stay leaking, not this on and off thing. I will keep on investigating but will update once I find it. thanks.

[NolimitZ32]

With my limited exposure to your situation it seems that the likely culprit would be the fuel damper since it seems you are maintinaing fuel pressure even when it's leaking. As for how it leaks I couldnt even begin to speculate.

[archny]

I have left the car at my friends mechanic shop and of course no leak. I will update if something new comes up. Thanks.