Engine Cover - steveb
Like most new cars today, the top of the engine in my vectra is covered by a plastic clip on cover - that apart from making it look neat and tidy - as far as I can see serves no other purpose.

The reason I am posting this is that a number of pipes and wires run out from under the cover to other parts of the engine bay, and as the edge of the cover is quite sharp, there has been chafing to at least two pipes and one set of wiring. This has necessitated the liberal use of black insulation tape to cover the pipes/wires and protect them.

Given time I have no doubt that material damage would have been caused by this cover - all for no other reason than aesthetics - under the bonnet !!

Engine Cover - RichardP
I pulled the engine cover off my 2000 diesel vectra as like you say it served no useful purpose whatsoever. There was some foam attached to the underside of the cover which I presumed was some sort of acoustic barrier. having the cover makes little if any difference to the engine noise. I like to see whats going on under the cover anyway, makes it easier to spot any leaks etc.

Value my car