Hi there, I wondered if anyone on here might be familiar with the symptom I have. Previously the egr coolant hose was split so I bought and fitted a silicone replacement. At the same time I decided to give the egr valve a clean and also fit a blanking plate. Starts and drives fine, the problem I s that when idling there is a deep tapping noise, from the outside it sounds like there is some music on in the car with a heavy baseline. Perfectly timed apart, sounds like a pump pulsing. With gentle revs it goes away. A quick off then restart and it went. Next journey back again. Could it be the Vac pump? Anyone heard of this? Could it be related to the blanked egr? 54 plate 2.0D 72k miles.