Hi, I have a 2007 Seat Altea that I have owned from nearly new. It is fitted with a 105hp 1.9tdi Pumpe Deuse turbo diesel with the BXE prefix. The car had a service at a VW dealership at 27,000miles and I was told that there was a small oil leak at the lower intercooler pipe seal, as the car was still under warrenty the mechanic said I should take the car to a Seat dealer which I did, the repair lasted about a month before oil started weeping out again and a whistling noise appeared. The car has now done 41,000 miles but for the past 5,000 miles it seems to be losing boost pressure at between 1,500 to 2,000 revs which is when it whistles, it sounds like a balloon losing air. It is obviously the intercooler seal that is the problem but try as I might I can't fix it. The new seals appear to be of a softer material and seem to be loose when in place, by the look of them they are manufactured to seal at pressure. VW recommend installing them with red rubber grease but that is no better. I have tried using PTFE tape under the seal which makes it a tight fit but that only helps for a short time until it blows the grease out. I want to avoid using a permanent seal as I may have to pull it apart later on also I don't want to use anything that may end up going through the intake. I am now on my fourth set of seals and getting sick of it. I can't find any other updated seals although the problem appears to be widespread, any help would be greatly appreciated, Thanks for your time.