Opel astra H engine light

[gilley_cro]

Hello,

I have problem with engine light in opel astra H (1.6, 16V ).

First i need to say that car is driving perfectly fine, but the engine light keeps turning on. It stays on for few days, than it wents off and it goes like that for a few months now.

Local mechanics didn't help me, so I bought diagnostics myself to check for error.

What diagnostic said to me is next:

P0170 Fuel trim malfunction( bank1)
P0300 Random cylinder misfire detected
P0304 4th cylinder misfire detected


It also says that lamp will not be illuminated becouse of code P0304 , so I guess the problem is in that Fuel trim mafuction.

Any guess what could it be ?