I am trying to find a movie I saw part of on TV around my early teens, which would date it between '80 and '90, give or take. I am pretty sure it was a movie because of its length, as I was not allowed to stay up until the very end. I didn't know the name or any of the actors. It was in English and not a B-movie, I think, but the latter could be wrong. It was aired on one of our local channels, so no idea where else it could have aired on.
What I remember:
There was an empty room which was unremarkable except for a menacing hole in the floor approximately in the centre of the room, about a meter or less in diameter. It looked like it was created by some alien creature or it could have been an alien creature in itself. The room and the hole were discovered by a couple or family, moving into the house to which the room belonged. I don't remember any children, except for maybe a baby.
At some point, it was revealed that the hole was actually a deep vertical tunnel which had (small) teeth inside, or the tunnel wall resembled something caterpillar-ish, with ringed protrusions going all the way down. I also think it changed from a closed hole to an open-mouthed tunnel by itself. It didn't move or interact in any other way, it was just there, looking menacingly, and through some event it was shown to be open sometimes. And, not really sure but, the open tunnel meant something was on the loose, though it was never shown what until maybe near the end of the movie. It wasn't an obvious horror movie with blood and gore, or at least not as I remember it, but it did have scenes with bad things happening because of the hole or whatever creature was linked to it. Someone may also have gotten swallowed by the hole, but that is just a fuzzy memory.
A second part I remember is that someone had visited the couple in their new house and taken pictures of the hole with the intent of starting an investigation. But that person got killed because, while driving home in his/her car, the pictures on the passengers seat self-combusted violently and the driver, not being able to escape, was burned alive. I also tend to remember a lot of bees in this scene, somehow involved in the driver not being able to escape the car, but I am probably confusing this with a scene from another movie/show. They showed the body afterwards, when the tragedy was discovered; the car itself wasn't completely burned out but the person was and that did scare me as a kid.
It definitely predates The X-Files (which has an episode about killer bees in a car, I think) and I never came across it again. Various searches with terms from my recollection turned out nothing, even here on Stack Overflow, 'hole in the floor' doesn't have many exact hits.
So, hopefully, this rings a bell for someone, or others' search proficiency might turn up something.