It first got noisy years ago I'm guessing at about 270-300k km so I ordered both the Pierburg pump and check valve from FCP but only had time to change the valve at first and surprisingly the pump got quiet again so a year or 2 later I sent the Pierburg pump back! I wouldn't doubt that the original would still be good if I had caught the valve earlier and the pump hadn't got a good dose of exhaust through it. So learned that lesson!
I'm thinking too that the facelift air pump is much more expensive because it probably is much improved over the previous years. Anyway, original is back on and much quieter with some lube sprayed through it for now.
