Yesterday I just got my 2003 955i back from its 24,000 mile service. Prior to taking it in I would have an issue with my idle upon arriving to a stop sign and backing off the throttle only when it was very cold out and the bike had not fully warmed up. But as of late, I never had an issue with it until I picked up from getting serviced. I got a call from the mechanic and he said after he did the service he took it around the block and every time he came to a stop or would rev it to no more than 6,000 rpm and let go it would not be able to hold at idle. I took it home and it did the same thing. I would come to a stop pull in the clutch and the needle would fall below 1000rpm and try to recover to 1500rpm for idle and would fail to do so and stall. Oddly enough whenever I start the bike and idles and runs fine. It just fails to hold idle after the rpms are up. Is this an engine failure or possibly something else.