940 threatening to stall at low revs

I have a 1992 940 turbo.

When the engine is warm, at low revs, it's threatening to stall. The
rev counter drops to 500 and, naturally, you try to get this back up by
feeding some throttle through. But this doesn't always help, almost as
if the engine's flooding. If I have the car in gear with the clutch
down and try to lift it and gently squeeze the throttle, the revs,
having got back to around 1000/1200, fall as if the car is about to
stall. However, it's not stalling.

All very strange and I'm really not sure what's going on. I've got the
car booked in for a trip to the mechanic later this week but would like
to have a clearer idea as to what might be wrong. Anyone got any ideas?

Tim

 

A good place to start is to clean the throttle body and the Idle Air Control
valve under the throttle body. Usually the symptoms are worse when cold as
those two get gunked up, but not always.

Mike