PTC Nipple smoke test for vacuum leak

[i4gotmyid]

So I have been chasing down a vacuum leak in my 1999 s70 T5. I put smoke into one of the small Air Intake hoses with the MAF end sealed with a glove. I ended up with a ton of smoke coming from gasket of the PTC nipple. The rubber grommet felt hard as a rock so I assume it was not holding a seal. I purchase a new hose and noted that the gasket was softer, but didnt see that much of a difference. Back to the smoke test, and voila, still smoking from the PTC gasket...I guess my question is, "is it supposed to be a complete seal?" As I purchased this from the dealer, I assume it could have been sitting on the shelf and the gasket dried up. I was going use a hi-temp RTV silicone to seal the gasket and call it good, but figured I would ask if it is supposed to completely sealed and if I would be creating more problems by doing so.

[Chuck W]

Any leak after the MAF sensor is not good, as it's already been metered. Any leaks can throw off the system calculations for required fuel.