Hi i recently bought an audi a3 an when driving it had a sudden loss of power in each gear having turned the ignition off then on the problem clears any ideas

Your problem is with eather the actuator on the turbo then tend to stick a quick clean and fvree up with a suction pump can solve it, or the second is the veriable veins on the turbo sticking Forte fule addertive can clear it up but the best solution if ut competent is remove the turbo strip it down soke the veins in penertration oil this will free up the carbon build up and ensure the turbo runs correctly.

the reson this happens it the turbo has sliding veins that extend at low rpm to improve low end power and the retract when the turbo is up to speed, if the veins do not retract the engine goes into over bost protection as the turbo is adding to much air into the system normaly a bar over the standard pressure hope this helps

My Audi A3 from 2002 has a problem with the EPC. I have been to authorised service but they could find nothing wrong. When the EPC stays on after starting the engine the authomatic accelaration - I have no control. The engine accelerates by himself and somethimes it stopps.