Hey guys, just bought an altea 1.9 tdi bjb engine code, 64k full service history, love the car but has just developed a little fault, engine management light came on other day, plugged code reader in and code p0236 turbocharger/supercharger boost pressure sensor circuit a came up, changed map sensor and cleaned egr but to no avail, car seems to still respond ok but at the moment its spewing black smoke out the rear, when driving you can also hear the turbo, not sure what the problem is, any help would be much appreciated