Raw fuel smell when key turned, but before engine start

So, I've been having a problem for a while with a raw fuel smell coming from the engine compartment. With the vent open, it's very strong in the cabin, but with the A/C on recirc, there is no smell. After driving for a while, the smell goes away. It lasts longer on cold days, but even on hot days (central Arizona, around 95-100f) the smell is there for a few moments if the car has been off for more than about 12 hours.

 

I took it to the Subaru dealership several months ago when this first started, and they said they found leaks where the fuel line connections were, which they fixed, but the smell continued. I took it back, and they said that there was one fuel line in the front that they were unable to get to because the clamp was upside down, and they couldn't get a tool in there to loosen and replace it. They would have to remove the manifold to get to it, and that was a bit more than I could afford.

 

Jump to today, when I was under the hood checking something unrelated - windshield sprayer hoses. I turned the key enough to turn the sprayer on (checking for a leak in the hoses), and I could suddenly smell fuel fairly strongly. I didn't start the engine, and it had been off for at least 24 hours.

 

So, here's my question:

 

Does the fuel pump turn on before the engine starts, and could the leak be there, or...what? I don't have very much experience with Subies. I wouldn't even qualify for my shadetree badge, but if I know what the problem is, maybe it will be less expensive if I have to take it to a mechanic and can tell them where to start looking.

 

Thanks in advance

Just for my own curiosity.. I wonder if you can trace the smell to under the rear seats? I wonder if you have a cracked fuel pump housing like I had?

 

https://legacygt.com/forums/showthread.php/cracked-fuel-pump-housings-need-recall-259756p2.html

No, it's pretty localized to the driver's side under the hood. I don't even smell it in the cabin unless the air vent is picking it up.

As a side note, the engine was replaced about 5000 miles ago with a used engine, which had about 70,000 miles on it (the car itself has 124,000). I wonder if there could be something there that wasn't reconnected solidly? Whoever did the change-out did try to reuse a one-use clip on the cooling system, which caused a leak. Maybe they took a shortcut here somewhere?

Does the fuel pump turn on before the engine starts, and could the leak be there, or...what? I don't have very much experience with Subies. I wouldn't even qualify for my shadetree badge, but if I know what the problem is, maybe it will be less expensive if I have to take it to a mechanic and can tell them where to start looking.

 

Thanks in advance

 

When the key is set to the on position (just before ignition) the fuel pump will prime and pressurize the fuel lines, it'll prime for a couple of seconds. The fuel lines are a bit of a pain since most of them run under the manifold (from what I remember) and overtime the little clamps start to loosen and you get a strong fuel smell. I had this issue and I tightened all of the clamps while my engine was out... I don't think it's too much trouble taking the manifold off with the engine in the car but maybe someone else can chime in.

Like 200kSpecB said, when you turn on the key (but don't start), it will prime the fuel pump pressurizing the line. If you smell fuel one of your lines has a small leak, most likely a hose under the intake manifold, but could be before too.

 

Let you car sit for a while (overnight) and open the hood, and have some one prime the fuel pump while you look for any wetness on the fuel lines.

 

Removing intake manifold is not hard, but is about 2hrs worth of work, can be done easily in place.