hello guys,my dad just purchased the m6.very powerfull car bt after the puspakom checked,then the problem rised..they opened up the engine cover to alocated the engine no then they fixed back....later after i want to start the car,a loud sound from the engine bay been heard.once the engine starts,theres no sound......this been troubling me n i send to ultratune to rectified the problem n they asked me to changed the vanos which doesnt makes sense to me....so,pls guys help me on this matter or a good workshop indead,thanks!