Black Smoke

[m8gic]

Hi guys below are my problems for my Audi A4 TDI 2002

• When Idling and car has warmed up. Loads of black smoke comes out when it is revved hard (actually marks the road with black soot ) and at night against othalso smokes when pulling away from lightser cars headlights
• Poor Mpg (average 30-35 mixed, driving like an OAP)
• While driving can sometimes feel a slight hesitation(usually under 2k)

I had my friend to have a look at it and he could not find any error codes but he was not using VAG COM but a hand held diagnostic tool.

He disconnected the MAP sensor (not maf) and we revved the engine hard and this produced hardly any black smoke , As soom as we reconnected the MAP and revved it hard the black smoke came back and was quite a bit.

Disconnected the MAF and no change apart from no turbo when it is driven disconnected.
The Turbo wastegate ppe seems to be fractured.

The EGR valce and MAF could also be the cause.

Can anyone help me out please as I want to get rid of the black smoke and improve the cars MPG and most be MAP sensor related as it hardly smokes when its disconnected?

[NICE1A4]

Hi Mate, might be of some help, but the last time I saw these type of symptoms was with our other car, a 130Tdi Passat sport. A hole appeared in the turbo boost pipe and as a result less air was getting through to the combustion chamber resulting in thick black smoke. Remeber when you close the tube on the bunsen burner? black smoke! Saying that, there was an audible hiss when you put your foot down at the same time as the smoke! Does this happen?

[spartacus 68]

EGR valve can become blocked. Can be cleaned - including the inlet manifold.

I'd use a can of Forte diesel conditioner straight into the fuel filter and run it hard in 2nd and 3rd gear. You'll need to replace the fuel filter afterwards.

[rocket1]

had similar thing on my golf tdi and that was due to an intercooler pipe coming off and loosing boost pressure. as soon as it was refitted was like a new car again.