406 erratic idling

Hi,
I have a problem with my 1997 2.0 auto 406.
Sometimes the idle is very erratic, and it sometimes cuts out completely.
This seems to happen most often after a fast run, eg at a roundabout coming
off the motorway.
I've read several posts reporting a similar problem, and the advice seems to
be "clean out or replace the stepper motor".
Is this a job I can do myself, or do I have to give more money to the
dealer. I've already paid for the privilege of having them read the ecu, and
tell me it's not stored any faults..
Thanks in advance,
Martin

 

This is cut and pasted from a previous reply of mine to the same
question. Hopefully it'll make sense.

I use aerosol brake cleaner. Make sure the ignition is off and remove
the stepper motor (small torx screws,and can be tight). spray the
cleaner over the piston and allow to dry. Also spray into where the
piston goes, but not too much. Put the stepper motor back. Start the
car and rev it to 3000 for 10 to 15 seconds, just to clear the cleaner
out. Now allow to idle. If it stalls, or idles too high, it needs to
be initialised.
Switch off the engine, switch on the ignition, then off for 10
seconds, then on for 10 seconds then off. Now start and see how it
idles. If necessary repeat the operation. If it is still messing
about, switch off and disconnect the battery, then the ECU and leave
disconnected for a minute (make sure you have your radio code!!). then
reconnect the ECU, then the battery, then repeat the initialising
operation again. That will hopefully do it. If not then you need a new
stepper motor.

 

Thanks for the advice, I'll give it a go and let you know how I get on,
Cheers,
Martin