Decreased engine power: The turbocharger helps to force more air into the engine, which increases power. If the turbocharger is failing, the engine will not get the air it needs and performance will suffer. You may notice a lack of power when accelerating, towing, or climbing hills.
Black smoke exhaust: The turbocharger helps to regulate the amount of fuel that is burned in the engine. If the turbocharger is failing, too much fuel can be burned, which will create black smoke. You may also see black smoke when shifting gears and accelerating.
Unusual noises: A whistling or whining noise could be a sign of a turbocharger air leak. A clunking or rattling noise could indicate that the turbocharger is damaged.
