1997 Caravan sudden loss of power

My wife was coming back from an appointment today in her Caravan. It’s a 97. Last year we put in a rebuilt engine. Today when she put her for on the gas the engine would rev but not accelerate. She said she though she smelled something burning, and some emitted from the drivers side of the engine. She pulled over and the engine idled. She thinks it’s blown head gasket, of course everything to her is a blown head gasket. My feeling is that it’s transmission related. Before this happened we did have a service engine soon light that was tripped by an exhaust sensor.

Any ideas?

How long did she rev the engine for? If you’re lucky it went like this: you had a sudden catastrophic loss of transmission fluid (producing the smoke); the engine was revved only for a few seconds and then pulled over and turned off shortly afterwards. If I were a betting man I’d not take the bet, but the transmission could survive that sort of thing.

So was the van towed? Has anyone popped the hood and looked under there? Has anyone checked the transmission fluid? If so, what was the level? smell? color?

The ses light is likely unrelated - but there is no “exhaust sensor” - someone probably said something about an O2 sensor. If you want advice about that you should post the actual code - but I think you have bigger problems.