Hissing sound from primary injectors, air or leak?
 

as the title says really. Is this leak between the big rubber ring and out, or is this air I hear coming out?

Bump! I changed the o rings on the air bleeds, tried spacing out the grommets with an o ring, nothing helps.

As far as I see, I need new injectors and maybe a new rail as well, the bolt hole area might be bent for what I know.

these are stock injectors?

Hold a long length of vacuum line to your ear and use it to probe around. The sound noticeable changes if you get close to a vacuum leak.

Sorry didn't mention it, but the sound comes in pulses like when the injector is... injecting gas into the engine. Conventiently telling me the leak is on the manifold side, not the fuel rail side of the injector.

I tried swapping the o rings on the air bleeds as I said, same thing. It is slack in the injectors up/down (you can turn them a bit easier than the secondary injectors).

I haven't tried swapping primary and secondary, I take they are the same on the FC?

Stock injectors btw.