2003 Zetec Fiesta. For the last few days, I've been thinking that the exhaust has been blowing a bit. Only doing it at low revs, which seemedodd, but not impossible. But I've just noticed that it only does it when the steering wheel is turned left or right. Tickover drops a couple of hundred RPM, too, but recovers. So now I'm not sure where the noise is coming from at all. Is some switch in the steering mechanism playing up sufficiently to make the RPM drop so that it labours so much that the exhaust blows? Or is something so badly nackered in the steering that it sounds something like a blowing exhaust?