I have a 99 with a leak that looks like it is coming from an elbow fitting for a heater hose. The fitting is at the right hand bottom of the plenum. I have not found much info? I wonder if anyone has replced this part? looks like lots of gasket problems with the intake. This fitting looks like it may be a SOB. Any info will help.
Intake leak? on 1999 Buick Park Avenue
Try performing a cooling sytem pressuer test first and that may point you in the right direction. There are 2 of these "L" shaped pipes and if its the one Im thinking about it goes into the side of the lower intake. These pipes usually dont leak unless someone replaces the lower intake gasket and does not replace thethese pipes. Your probably right that you have a lower intake leak but it may also only be a upper intake plenum leak. Both leaks are very common. Clean off the area and monitor it to verify where the leak may be coming from if you dont want to pay for the pressure test.