Black Smoke and stumbling on acceleration

[mark_88_turbo]

Hi All,
over the last few weeks my A6 1.9TDI Avant has had black smoke coming from the exhaust under acceleration. It also stumbles like it's misfiring.
Does anyone know what this could be please?
Any advice gladly recieved.
Thanks,
Mark.

[mark_88_turbo]

Just had the sensor changed but it's still smoking. I've have a quote for £1500 to get it fixed .
Could this be a turbo?
Mark.

[fenboy]

Not sure. Could be a dodgy inlet pipe. Hole in it would cause some black smoke. Could also cause a misfire effect as would alter air fuel set up. Is the management light on? If so get it read. Most garages can do this nowadays.

To be honest could be many things but intercooler pipe is common for black smoke and loss of power.

[leigh195]

Is it similar to any of the symptoms like in mine.
My black smoke and no power problem

[mark_88_turbo]

Thanks for the responses. I was told it was either the turbo and the diesel pump, but they were both tested and they're fine. It seems to have stopped for the time being so fingers crossed it's ok.

[yaman]

As already mentioned by fenboy, check the joints on the inter-cooler piping.

Also, you might need a new injector wiring-loom.

Was any faults logged on diagnostics?

Regards
Jim

[mark_88_turbo]

There were no faults on the diagnostics. The garage recons it could be a dodgy / old exhaust system. It's been on the car from new.

[Jimmy B]

One of the injectors might be breaking down? Check this to make sure all the injectors are running the same amount of pressure - had a similar problem on cold start and when coming to a standstill - but they are expensive to change!

[mark_88_turbo]

Thanks for the info. Everything seems to be expensive to change!

[tone35]

i think leigh195 mentioned this already, but have you tried blanking off the egr valve? my 1.9tdi had similar blacksmoke and hesitation when idleing and under acceleration.

to see if it improves things remove the rubber hose to the egr and temporarily blank off both ends with gaffer tape, take the car for a spin and see if that sorts it out. mine has been perfect since i blanked the egr off. also, the egr problem didnt show up when reading for error codes.