Oh my! I feel your pain! I wish there was an easy way to get rid of these pesky creatures. My father and son have so many adventurous memories of all the moles through the years. It really is like a cat and mouse game or as mentioned Tom and Jerry Tale. I wish, I would have taken a picture of one of holes they filled this season. I swear, it looked like the size of a bear hole in hibernation. I literally gasped aloud upon seeing it for the first time. It sat along the forest line, surrounded by poison ivy. Yep, my dad got a bad case for awhile there. Usually, he is good about warning us all about its whereabouts, but his year, thanks to the mole problem, alas he felt the wrath for awhile.
P.S. Never heard of using car exhaust. Wonder if my dad has since he is so old school.