Thriller movie

I hope yould help me. It is a thriller movie about hostage taking place in a green van. The first scene of the movie was a heater (used in boiling water) with diffused smoke coming out which means that the water is boiling. I really forgot the rest of the movie. What I can remember I think was that it was a hostage taking in a green van. This movie was not famous. I hope you could help me. I just want to reminice my teenage memories and this movie was one of them. Thank you!