I am trying to help get a vehicle back in working order for my girlfriend. Her Saturn is throwing the P0366 code. It has not sent any check engine lights. We had a dealership friend look and confirm the code.
That being said. The symptoms are vaguely similar to bad spark plugs or transmission issues. It is losing power. Step on the gas and it gets almost no acceleration. The vehicle shutters are specific speeds. Dealership friend did tell us that it IS possible that it was just excessive carbon buildup in the engine. But i don’t know how to confirm that. He mentioned running seafoam through the engine as a carbon cleanup? I could have vehicle oil changed And do a carbon cleanup through an oil change facility as well. I believe it is due for oil anyway.
What I am looking for is some help diagnosing the specific problem and the possible cost of repair. Any help would be greatly appreciated.