The EGR is nothing more than a valve that opens and closes. Remove it and check for carbon build-up. Check both the EGR and where it connects to the intake. The intake will often times carbon shut. As far as operation, once it is cleaned, apply vacuum to it to see if the valve responds by opening and make sure it seals closed when the vacuum is removed.
Tuesday, December 28th, 2010 AT 3:21 AM