A friend has an '00 323 that has stalled twice in recent weeks, once today,
and the Service Engine Soon light comes on during the event, but then goes
out again and remains out.

She pulls to a stop sign, waits her turn to proceed, then the car stalls
when she attempts to go. The symptom set she described to me sounded as if
there was a problem delivering fuel, but since the Check light flashes on, I
elected to check for stored codes before lining up my wrenches. The only
stored code is P0340, which translates to a failing cam sensor.

She also says that under load -- freeway driving -- on long inclines, the
car does not hold its speed as well as it once did, and she feels a need to
put her foot into it more than she remembers, and this prompts a downshift
that she describes as very harsh. I don't know what this means because a
single gear change from 5th to 4th shouldn't be a memorial event, but if the
car was dropping from 5th to 3rd, that would be something to write home
about. She does not mention that the Check light comes on during this kind
of event.

Obviously, if the cam forgets where it is then the engine is not going to
run well, and this could explain all of the symptoms with a single cause.

Where does the cam sensor physically live on the M52 motor? What is the
price range for a new one?