Ok,i didnt bother testing the valve because the blanking plate turned up today so fitted that whilst leaving the valve pluged in & cable tied to the engine hoist eye but its still hanging back.
Went to local garage to have the codes read which were multiple cylinder missfire,egr flow too high,egr too low & something about an imobaliser prob.
I should point out that I didnt do the plate till after I had the codes read so I can ignore the egr codes.
Could all this be the coil pack,could it have anything to do with the fact that I have a small crack in plug no.4,is there any thing else that might be causing it,this is a big problem now.