I'm in the UK and I've got an X-reg (2000) Carisma 1.8 GDI Equippe Auto
(4G93 engine) that's playing up.

Symptoms are:

When starting from cold, instead of just sitting at a fast idle the revs go
up to about 2500 then drop to about 800, then go up, then go down, up, down
etc., etc., oscillating between the two values for about 20 seconds, then it
settles to about 1000.

Putting it into either "D" or "R" the revs drop right off and it almost
stalls. Sometimes it does actually stall.

On moving off, the car accelerates to the point where the auto box wants to
change gear but during the change the engine races (on a manual box it would
be like putting your foot down on the clutch but without lifting your foot
from the accelerator) so that there's a jerk as it engages the next gear.

When the engine reaches normal running temperature most of these things
disappear and the car drives OK. The only thing that remains at normal temp.
is the stalling. Sometimes, waiting at traffic lights for instance, I'll
have the car in Neutral. When the lights change and I put it back in gear,
the revs drop off and it almost stalls - sometimes it does stall. And
sometimes, when approaching junctions, it'll stall before it comes to a
stop.

It's done 50,589 miles and had the transmission fluid dropped, box flushed
out and new fluid in, along with cambelt change and everything that should
have been done on the 54,000 mile service, nine months ago at 45,490 because
the dealer said that it was 54,000 or 5 years, whichever came first.

I rang a mechanic today who's going to have a look at it on Wednesday, but
describing the above to him on the phone, he reckons it could well be the
Idle Control Valve Stepper Motor - what do you guru's on here think?

Cheers,

Fred