1986 300SDL: x-shape vacuum hose connector in trunk?

[TonySz]

Looks like my vacuum pump in my 86 300SDL's trunk is on the way out. It sounds like it's dying a slow death and only working 5% of the time. While putzing around in the trunk I noticed an X shaped connector for the vacuum lines up the right side almost over by the fuel door. Weird thing is only 3 (yellow) vacuum lines were attached. There was one open port on the connector but for the life of me I couldn't find a loose vacuum hose. The open port doesn't appear plugged. Am I right there should be another vacuum line, totaling 4 lines, going to that connector? Thanks.

[Gilly]

Can't remember exactly, possibly the X is supposed to plug in to the fuel door lock itself, is that possible? Or does one of the lines already run to the fuel door lock element?

[TonySz]

Thanks Gilly. That was exactly it. Like an idiot I was staring right at the thing when it hit me like a brick wrapped in gold foil. Yeah, the open port was indeed for the fuel door pod.