This engine was believed to have come from a 1998 Jeep Grand Cherokee, where it was rated at about 195 horsepower. The Jeep 4.0 inline-six is known for durability but failed here due to neglect.

Jeeps have a reputation for being tough and comfortable on and off the road. Over several decades, though, even they've made some engines that aren't great.

I'm a woman who takes driving rather seriously. I started off as a mechanic before doing delivery work to pay for college, racking up hundreds of thousands of miles of driving local and long-distance ...