fuel injectors/ vacuum leak...

[mcat]

can the bottom of an injector cause a vacuum leak, yet not leak any fuel?

 

[71ruster]

I say yes there are o rings on both end of a injector top for fuel and bottom for vacuum

 

[blown71duster]

We use a smoke machine to check for vacuum leaks at our shop . I have seen guys use carb cleaner, propane or even water sprayed at the suspected leak.

 

[Map63Vette]

I'd think it's possible. It's not like the whole intake system is pressurized and going to squirt fuel out if the lower O ring is bad.

 

[TrailBeast]

Oh yea they can, because fuel in an injected system really isn't a liquid like we see with carbed engines.
The injectors fire a timed mist right before the engine sucks it into the cylinder, so yes a vacuum leak can exist without fuel showing.