black spark plugs

Hi friends, the last days when the car starts, did well but there are a very strong gas smell in the garage and it seemed like there are a very rich mixture in the injectors.

The spark plugs appear like a black velvet coloured, not greased but black as well.

Anybody knows what´s wrong now?, is there any plug i must clean? is there any relay or special device i must look it? Any thougths?

It´s look like the automatic choke it´s wrong now.....

Thanks in advance