When my MY00 gets warmed up the tickover is extremely rough (this has been happening for about 2 weeks now.

The car is about 500 miles short of the 60K service - although I plan on changing the air filter for a high flow replacement panel before then.

I have also just realised that this has only started happening after I replaced the offside blanking plate to the bonnet grille - the one that sits over the filter box.

any opinions appreciated.