Anyone have any idea what they used?

Did it smell/stink? Methyl chloride and ammonia (not at the same
time!), concentrated and hot, make real good paint removers. But
they'd both stink to high-heaven.

[Carbon tet]
Not really caustic, but toxic enough it got yanked
off the market, as did its replacements,
Trichloroethylene and Trichlorofluoroethene

What do they put in today's carb/brake cleaners? It smells like
Trichloro-something.

Tim.