have a scan on it most probably come up with p0400 code get some redex to clear out fuel system if not work its something to do with the fuel system
It could be a simple missfire. Mine did it a few years back because of damp weather.
Citroen charged me £35 to diagnose the problem but couldnt tell me what it was.
It is back on now and causes me no problems. It is just an engine management fault.
If your worried get it checked out but be prepared to pay for it.
Citroen Xsara Picasso 2006 LX - F22 (20Amp Yellow) - fuses behind panel below steering wheel to the right.
it is the side airbags
There are two places for fuses on the Citroen xsara Picasso the main ones are to the right of the steering wheel behind a little storage area just pull the recess out and the fuses are there the other is under the bonnet.
I think you may be talking about the dashboard dimmer switches.
under the fuse box inside to the right of the driver. Black on on the left. the right one is the hazard lights relay.
on top right side of dashboard there are two buttons one looks like a book the other arrows, they change date/time on Picasso
Remove the fuse board cover at the right hand side of the steering wheel, the switch is located behind the mass of cables, a quarter turn to the left will allow the switch to be removed.
Service Light Reset - Citroen Xsara (1997 on) Using button located at the right hand side of the speedometer dial. Switch the ignition off. Press and hold button. Switch on the ignition. Keep the button depressed Service Interval and "spanner" symbol will illuminate for five seconds.
Depress computer button on end of right hand (Wiper) stalk several times until required data is displayed.
Under the passenger's seat for a right-hand drive car, or under the driver's seat for a left-hand drive car.
anti roll bar
Might be worn drive shafts or loose wheel nut