Black Smoke Audi A4
 

Hi all

I have an Audi A4 1.9TDI. It has been emitting puffs of black smoke through the exhaust. I took it to my mechanic who did this

changed oil
changed oil filter
changed air filter
changed fuel filter

this made little improvement but then the smoke came back. My mechanic then suggested me to try and use Fuel Injector cleaners and go for motorway journeys which I have been doing for the last 2-3 tanks with just little temporary improvement. (Used STP injector clear twice and Forte Injector cleaner once)

PLEASE HELP ME AS THIS IS QUITE FRUSTRATING and I know if I take it to Audi they will rip me off as always.

Thanks for your help

try changing where you buy your fuel from, dirtier fuel leads to dirtier exhaust. and adding injector cleaner will also temporarily increase smoking, because it is causing the engine to burn off some of the sludge built up on the valves.

other causes could be leaking head gasket, burning clutch (is your car a manual or automatic?)

Thanks Alkival.

Yes I have also noticed when I added BP Ultimate the smoke was reduced ad when I used this Total normal diesel, it came back. So, I will make sure to use the BP Ultimate oil (previously I have been using Sainsbury diesel for the past several months).

I have also noticed that the smoke is minimal in the morning but excessive in the afternoon and night (altough not much visible at night)

it is manual.

thanks