Hi. I wonder if anyone can help me. I have a Audi a4 2.0 TDI Quattro 170 hp. The issue is that when accelerating theres no power and thick black/sooty smoke comes from exhaust until the turbo boosts at 3000 rpm, then the smoke clears and runs fine until you come to a hill or hit under 3000 rpm. Then the power dies and the black smoke comes back. Checked fuel filter, air filter, injectors, airflowmeter, intercooler and pipes.. i have checked everything i can come to think of. The car is chipped, and have about 210 hp as is now. The EGR is blocked. The problem occured overnight, and the car is impossible to drive. Any help would be appreciated 
