Hi I have a peugeot 206 1.1 2004

change mechanics --or bring back and have them fix correctly when they did the engine work doesnt sound like was done correctly and now you may have a bigger problem

Back to the basics...have you retraced the firing order?

It's normally the wires in the loom that go to the injectors
or a fault on the ecu

Sounds like vacuum leak, bad coil pack, cam or crank sensor. None of which should break your bank unless its hard to get to.

is your check engine light on or has it been on recently? sounds like your cpu is adjusting fuel mixtures if you have had your battery unplugged for a good amount of time youre ecu/cpu does this. Has happened to me quite a few times. it should stop after it does what it does, i would say a week max.

Try replacing the relay switch. Check and see if you have a Relay for the headlights/lights for your vehicle... sometimes the relays can end up bent and corrosion can settle at times...not sure why, but its happened to me several times in different vehicles...good luck!

Most likely cause is the potentiometer that the throttle cable operates. Its either got water in it, or has become corroded or worn. You should be able to get on from scrap to try. DONT disconnect it with the engine running or ignition on - it will cause a fault and have to be reset to clear it.
(Its the sping loaded round device on the end of the throttle cable)

Likely there is debris in the system that needs to be cleared. Many systems have a filter screen that becomes plugged up and needs to be changed. (filter, orfice tube or whatever ) also make sure reciever dryer is replaced as well.

this sounds to me as the throttle position sensor or the air mass meter

please send information of control computer for subaru forester 1997,