'84 GSL-SE
I did a fuel leak check after re-installing my injectors and fuel rail. I could hear a hissing sound, but after 60 seconds of pump running time, no sign of leaks. Is the sound I hear just normal flow through the fuel rail?

 

did you reinstall the spacer between the rail mounting holes and the block? I forgot to do that once a few years back
Make sure you have all the clamps tight, and you may want to switch to the screw type.

 

OH, it could be air in the line too.
Its been a while since I've worked on a 13b, is there a bleeder somewhere on the rail?

 

i got a hissing too from under my UIM too but i dont know what is is i think that its from the bottom metered air line on the TB but i have no idea where it hooks up underneath the UIM. sorry to steal this from you. are yo usure that it is coming from the fuel rail?

 

im assuming that this is happening under KOEO test and not when the engine is running?

 

Perfectly normal - that's just the sound of high pressure fuel flow through the rail and into the FPR.

Don't sweat it - if you were leaking fuel, you'd know it (and smell it). As an extra measure of success, pull a plug and make sure they're bone dry before starting it up. This guarantees you don't have a stuck injector that's leaking-down and spraying into the intake. HTH,

 

Wow, long time no see LongDuck...

 

holy ****, my second gen did this too...only after i redid my omp lines and cleaned out the throttle body, upper intake mani. redid the vac lines and i put it all back..and when i started her up i rev her to like 3/4grand and when i let go i hear a hissing sound, something like a blow off valve....its weird and i thought that it was something bad in the engine....i dont know what the hell that is, but then i read longducks reply and im not worryed....

:AA:

 

Now that you mention it Roundabout... I do not recall a spacer there. My rail is bolted directly on to the block (intermediate housing). Can you enlighten me on this?

I read about the injector leak test...but did not perform it. If I pull a plug as suggested by LongDuck, won't the rotor position influence what I see at the spark plugs?

Thanks for the feed back everyone.

 

Oh and yes, test was done with Key On Engine Off. Took me a bit to figger that out.

 

I have that same hissing on my FC. its does it after drive it sometimes too just a hissing under the UIM. I redid the injectors and put the spacer back and it still does it

 

the spacer is about 1/4 in thick and about 1/2 wide it goes around the top part of the injector between the fuel rail and the injector

 

I guess I did not remove that spacer as I did not see it as a loose piece.
I have it running now and do not see any leaks. Did a 225 mile road trip and all is well.

Thanks very much for the technical support!