Need some help here please.

I went to start my vectra b 1.6 this morning and the revs rose to between 3 and 5000 rpm.

I switched of engine sharpish and tried 30 mins later, over rev ving between 3 and 5000 rpm.

I removed the egr valve and associated pipe work and cleaned them with carb cleaner, I also cleaned the throttle butterfly.

Tried restarting and same thing.....I removed the pipework again from air box to throttle body...got a pal to start engine...same thing...i covered the throttle body opening with my hand and the revs descended to normal...ie..800 rpm.

AmI right in assuming air is getting in somewhere....or is it some sensor..ie maf sensor?

Any advice appreciated.