Hello everybody, I’m looking for answers here in the forum, but I don’t like it or I don’t understand it, it’s not impossible. 🙂 Seat Arosa 1.0 6H, built in 1998, 126.000 km (If further information is needed, I’ll be happy to fill it up.) On the situation: In the cold start everything runs great and it purrs and does what it should. As soon as it gets warm the idle problems I’ve already read here and elsewhere. At the intersection the speed drops. then often so deep that the engine runs out when I’m lucky it catches itself and then runs quietly on. To the solution which may not be possible: After consultation with the previous owner we have removed the right (from the front) thin vacuum hose that comes down from the air filter and see there, everything runs. Whether cold whether warm, the Arosa drives and the idle problems are forgotten. To the question: What is the function of this hose? What could be the real cause and what the better auxiliary e be? I would be very happy about tips or an explanation, at the moment I simply lack the idea where to start.