[beMtroubleYou]

how is your idle and do you smell gasoline on idle? Gas not exaust.

Might aswell just add this to anyone reading. Had the same issue. Car stuttered occasionally and hesitated on cold starts. Once it almost didnt fire up and the light up the DM. After restart it disappeared.

Did a couple WOT nothing strange, car pulls hard. Read codes. Nothing.

Then I started to notice hard idle and gas smell on idle. Took it to dealer. Valvetronic harness change. Then all codes appeared and pointed to valvetronic servo motor. After they changed that car didnt send codes but new vaules couldnt be coded into the valvetronic ECU(or ecu in valvetronic section). Then they changed the eccentric cam. And now car took in the new values, idles perfect and no stalling.

Point is, there could be hard malfunction that cant be read by codes / not saying this is your case. Just a heads up.