Curious to know if anyone can tell me what the black vacuum line that is behind my instrument cluster is for. This is on a 1984 2.2Ldiesel chassis, now converted to gas. The drivetrain is out and the speedo being upgraded to digital and I found a vacuum line, but there is no economy gauge. If you blow into it it comes out at the P/B booster
so its in the vacuum system. Why? All chassis from factory equipped but some not used?
Thanks for the insight.

TobiasMB
300SE, 300CE, 190/5.0