Possible EGR problem

Hi again folks....my 2002 Octy 1.9tdi turbo problems continue to baffle me. MAF changed, hoses checked, no change. Car has problems with turbo fully kicking in, often stutters whilst making a funny slurp noise, and can go into limp mode (when peddle floored) which is sorted by recycling the ignition. Lots of posts suggest that it can be an EGR problem or sticking vanes. Before I send it to the garage for tests and possible turbo clean, I want to try cleaning/testing the EGR valve. First question, am I right in saying that the EGR valve on my model is the one on the back left of the engine? It has a lever which, when pushed in fully, stalls the engine. If not, where is it? Secondly, is it right that you can test it by shutting off the EGR and running the car to see if it runs better? Does this damage the engine though?

Thanks folks