I have been having problems with my car. It runs very nice when i am travelling along. When i pull up at junctions and come to a stop. The engine light comes on. Then when i pull away, i have no power, hardly any revs. I travel a few yards with foot to the floor. The engine light goes off, and the car picks up, as if the turbo kicks in. This is the only time this happens, but happens at every junction. I have had the system tested and they have stated it's the EGR valve. I have replaced the valve and still the same. Now they are saying its the vacum, two little black boxes near the battery. A thin pipe leads to the ERG valve. Has anyone any advise on how i could stop this happening ?