So this morning on the way to work I changed gear at about 4000 revs to a loud whoosh/pop noise more aggresive than the usual Dv noise. Since then at low revs it sounds really rough and hunts around at idle nearly stalling before lifting the revs to 1200rpm. there is also a popping noise from the exhaust when coasting.
Now ive ran vcds lite with no errors recorded, unplugged the maf which made no difference.
What else can i check? would the dv cause erratic idle if it was damaged?