Don't ever do this at home! Or in the car!

It seems that children (and adults) with ASD/Asperger's tend to take things literally or at face value and have trouble with sarcasm, humor, emotional nuances, etc. My child is no exception. He is getting better at understanding humor and jokes, but he still often takes facetious or sarcastic comments as "real" or "truth". His Dad is especially good at causing intense confusion. Sometimes this is good exercise for our special boy and sometimes ... well, not so much.
For example: When it is 100+ degrees F and the whole family has just loaded up in the car that has been sitting in a broiling parking lot at the mall for a couple of hours, Dad should NOT remark,
"Hey! The thermometer says it's 110 degrees in here! Why don't we turn on the heater and see how hot we can get it! Wouldn't that be fun?!"

The result is that about 3 to 5 minutes later he says, "Whew! This A/C doesn't seem to be working too well, it's not cooling off in here." And the other two kids say, "It's REALLY hot back here!" And at that point I realize that ASD-Son Literal-Pants Boy has taken Dad seriously and turned the heat up full blast in the back seat!