car taking auto-acceleration & leaving white smoke with engine stop
I have a peugeot-206 1999 manual driving model, it has 191k mileage. it runs very smoothly when i am driving with very minimum smoke but when I stop at the red light even on neutral gear, it increases the RPM even I am not pressing the accelerator, it also automatically accelerates when on gears or driving but when it is stopped at red light, sometime it leaves lots of white smoke & sometime stops the engine & takes 6-5 key turning or 2-3 mins stuck on the main road but when it re-starts, the pick-up is extremely slow with some shaking but thereafter it runs very smoothly again with no smoke leaving.
I took it to the mechanic & he said some electronic problem but unable to say anything without checking everything :-(
Please suggest what to do & how much should this cost ? I want to use this car for another 6 months due to re-location to a different country.