audi a4 2.0tdi 2005
my audi has started belching out black soot like smoke when not excelerating like turbo lag.the engine
management light came on so we took it to a audi mechanis who changed the air flow sensor.it has
made no dirrerence and the light is back on a week later.any ideas please.
Black smoke is an overly rich air to fuel mixture (too much fuel). Could be a very dirty air filter, bad oxygen sensor, bad fuel injector(s), bad fuel pressure regulator, or bad fuel pump. Those are the things I'd check first. HTH. -Jim
Check in over at AudiWorld.com and Audizine.com - there's not a lot of information on the Audi diesels in the USA yet. We're about to see many more small block turbo diesels in the near future but we're not there yet.
it might help if you know what codes were stored in the engine management computer,way too many codes and procedures to even begin to guess.
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