The owners manual says nothing about mp3. That probably means no,
right?

It almost certainly means "no" although you might get lucky.

Ordinary Red Book audio CDs can hold up to 99 tracks. It's _possible_
that the CD you are interested in might be an audio CD with lots of
tracks, and be playable in your car. Total up the track lengths (if
that information is available). If it's less than 80 minutes you may
be in luck; if it's more than that, then it's very probably an MP3
(or similar lossy-encoded) disc and your car player probably won't
recognize it.

If it's MP3, you could buy it, use a PC to decompress the individual
..MP3 files into audio format, and burn them onto a set of Red Book
audio CD-R discs. Those would be playable in your car.