If you car is a mk5 golf gti... It is on the very front of the engine, attached to the intake manifold... silver with a grey top to it...
If you remove the throttlebody pipe that is attached to your intercooler, use your camera and take a video to have a look, then get a nice clean white cloth and if it is dirty wipe up and around the throttlebody... that will tell you if you have dirt.
But what kind of problems is it you are having, any engine lights come on, anno what your saying in your first post, what is your cars spec?
Also have you got access to vagcom?
if not have a look in the vagcom list and see if anyone is close to give your car a scan...