I have a Forge FMCL007P diverter valve fitted to my AGU engined car (not chipped) Recently I have been experiencing a less boost read on my gauge and the car has felt slower. I thought I would check the DV as I have had it for over a year. Looking at the diagram below, when I blow into part 1 of the valve pressure is leaked out. When I blow into part 2 it does not leak any air. Now part 1 is connected to the boosted side of the turbo so as a test I have swapped round the connections so part 1 now sits in the TIP and part 2 sits in the boosted area. Boost is now held fine and the gauge and feel is back to normal. My question is that, should the valve always be fitted this way round?? The seals look okay to me. Also I am booked in to have the car remapped next week, so is this valve going to be able to hold boost or do I need a stronger spring fitted?? Thanks.