EML coming on are common on aluminium chassis Plus 8's, usually something trivial. I'm lucky in having a good one, others seem problematic. I knock off the power switch under the bonnet whilst garaged. Try knocking the power off for 24 hours and see if your light goes out, most problems seem to be the Lambdas, unlikely IMHO anything to do with the Vanos, actually I'm almost sure the 4.8 doesn't use the Vanos unlike the 4.4's, keep us informed.....
