i know with new chips it takes a while to get the chip adjusted to the engine when you plug it in or onto the loom.
Just give it a few days or drive a bit, hot and cold start, hi revs and back to idle. Give the ECU some time to get used to the engine and "learn" how to control the engine. :wink ...
Mine has the same problem, it is the idling solenoid on mine have to switch off the a/c then slowly let it idle and then revs will automatically rise and idle at 900 or free gear and rev it up to 6000rpm Haven't got a replacement yet , any idea if any other car like BM or Volvo has the same ...