My 124 has been running at normal temp, just above 80. It takes it a while to get there, though (but not disturbingly long). Of course it doesn't get too warm while idling; if I leave it for 15 minutes it will usually get up to about 40, and then goes up to 80 reasonably soon after I start driving a bit.

I had noticed the slow warming up of my sister's TDI. I had to laugh ... she was telling me how she wished she could get one of those remote starters so she could start the car and have it all warm before getting in it to drive to work in the morning. I told her she'd have to get up darn early to press that button if she wants it "all warm." I noticed it does take a long while to get warm, even after it's been driven a while.

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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)