[:@]Hi. I am new to this forum and require help for my 97 A4 Avant 1.9TDI. I am getting intermittent loss of power especially when the accelerator is between accelerate and decelerate (coasting ) also when this loss of power occursI get a large puff of black smoke from the exhaust. Also and especially when going up hill under acceleration There is more than usual the ammount of black smoke and at times a serious loss of power as if the turbo has stopped working. Through trial and error I have found that if I switch the ignition off and then on whilst moving it seems to reset back to normal power. I have had oil changes and yhe injectors cleaned but to no avail. Also on the tripmeter it says "In 2 ". any help would be appreciated. Frustrated by what is otherwise alovely piece of machinery.
Regards. Les

 

You should have the codes checked, it would help. But from what you say it would seem that one of the pressure hoses might be cracked. When accelerating, you should hear a loud whooosh of the air escaping. The turbo does stop working, as the ecu shuts it down, to prevent engine damage. Turning the ignition of and on resets the system, so you regain power for some time. Check two hoses to start with, an "S" shaped one from the turbo to the transverse pipe, adn secondly a short straight one at the intakemanifold.