also the temp gaugewarning light came on. ? any ideas? just got it serviced.
had a flat battery Monday nite and jump started it ? could that have something to do with this ?

You did not say what was done when you had it serviced, so it is hard to say if the shop that did the service was at fault, but l would highly suspect that, especially if this has started happening after the service was done.

Have the car towed back to the shop, and have them check it out, if they are trustworthy, they will admit their mistake, or show you that another part has failed.

l had a Picasso 1.6. from new. It was plagued with problems. Warning lights coming on for no reason. The radio packing in and eventually replaced. Rough engine running. Eventually Motability took it back. l lost confodence in the car and would never have another Citreon

l have a c3, same thing happened to me, brought it back a few times, was told, to bring it in, when light is on, but by time l get to my citroen dealer, the light goes out. so it came on once, called RAC they towed me, it turned out l needed a new on board computer,as it was under warrenty, citroen paid. but have another problem- sometimes get into car, loud noise, turn car off, noise still goes, plus radio keeps playing, open fuse box, put cover back on & it stops- citroen cant find anything wrong

The jump start may have caused some computer troubles. Just disconnect the battery and reconnect it again (make sure you have the radio anti-theft code).
If this persists, check the fluids: liquid coolant, windshield cleaning water, engine oil (and gearbox oil if you can).