Whenever I've called my local Porsche dealers about an oil change, they always try to upsell me on an "annual service." The keep saying that as part of that annual, they will check and clear out the "drain lines" or something like that.

Any idea what this is? I was noticing something that looked like a drain near the front jack points. Is that something that can get plugged up?

Am I making any sense at all??

 

Most likely they are talking about the roof drain lines that run from the sunroof area down through the chassis and drain under your car. The openings are not big enough to get a leaf into but I could see there being the potential for blockage. The ends of the drain line look like the mouth peice of a flute. Interior water pressure opens the ends to release the water but when they are dry they appear closed. Simple enough.

 

Over time, those drain lines can clog with needles from evergreens, dust and other small debris, and sludge and slime. In my days with the VW Golf, I'd just squeeze the exit ports (which were near the hinges of the door), and the pressure buildup form a clogged line would clear out the debris. I could see them needing some assistance by gentle mechanical means if really clogged, but that isn't an 'annual' issue, more like a once every 5 years issue. Using air could disconnect an internal fitting (if they merge several paths by fittings) so don't do that.