Hi,

I have problem my stilo is go down when im drive, and start engine again and heave "Engine Fault" FiatEcuScan, show errors p0301, p0302, p0303. p0304 and somtime EVAP error.

Coils are new, ECU be repair, but, problem is not be resolved.
Stilo go down on gasoline and liqiud gas (lpg)

so you have some misfires on all 4 cylinders.
T hey are probabbly the result of something else ..like the EVAP error. i would get that checked first..If it's the evap solenoid ,you can check with FES while blowing through the evap pipe going into the intake.
It should be normally closed, and opens only when it gets signal from ecu /FES.


Also the erros can be caused by the LPG system when going from petrol to LPG.
i would erase all errors and use the car only on petrol for a few days.
then check again for errors.

or could be your head gasket as well, mines just blown in process of replacing it
i had multiple miss fires on all cylinders