So the good news is, I just replaced my idle control cable and it now starts and runs great. Even though it sounded smooth, though, the engine shakes the car a little more than I'd like ... I replaced the motor mounts about a month ago (haven't driven it much since) and decided today I should give the bottom bolts a bit of a tightening, just to be sure.
And ...

Yeah, the other half is still in the frame/arm somewhere. I've done a search and it seems my options are easy out or take the whole damn motor mount arm off. Would I be wasting my time to try jamming an easy out in there? I have a bad feeling that booger isn't coming out, seeing as I clearly overtorqued the bolt in the first place.
Oh, and here's a good question for me to ask (a little late): What's the torque spec for these bolts? I was tightening by hand with a breaker bar, obviously too hard.

You know, when I said it'd be nice if I could catch a break one of these days, this is not what I meant.

And when I get that fixed, I'll have to figure out why my car is a giant massage chamber.

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1987 300D, arctic white/palomino--314,000 miles
1978 240D 4-speed, Euro Delivery, light ivory/bamboo--370,000 miles
2005 Jeep Liberty CRD Limited, light khaki/slate--140,000 miles
2018 Chevy Cruze diesel, 6-speed manual, satin steel metallic/kalahari--19,000 miles
1982 Peugeot 505 diesel, 4-speed manual, blue/blue, 130,000 miles
1995 S320, black/parchment--34,000 miles (Dad's car)