Mystery Car 123 is none other than a 1985 Cadillac Seville. This style of Cadillac was produced from 1980-85. It’s “bustle back” was intended “to invoke the look of Daimlers of a past era.”1 People either loved or hated them. And speaking of hating the car, several people have noted that the engines used in these cars were not very reliable.
There were 2 engine options for that year and like the other poster said neither one of them had a good reputation. Standard engine was the HT4100. Optional was the 5.7 diesel. By 85 the diesel was a very rare. Both engines had similar problems where they were not fully tested in the ‘real world’ before they went into production so especially the early versions had significant problems. The diesels came out in 78. By 81 they had made several changes that really helped their reliability but there were still issues with the USA not quite being ready for diesel cars. The fuels had issues, the operators had to pay attention to things, and the service people had to be properly trained.2
Wikipedia agrees with these sentiments:
Sales were respectable at first, but disastrous experimentation with diesel engines (an Oldsmobile-sourced 5.7 V8, plagued with head gasket problems) and the ill-fated 1981 V8-6-4 variable displacement engine (1980s technology could not make it work reliably), along with poor quality control and lackluster performance from engines severely detuned to meet more stringent CAFE standards, began to erode the Seville’s standing in the marketplace. A new but underpowered 4.1 liter V8 was fitted to post-1981 models. It was prone to the block becoming porous and coolant mixing with the oil, resulting in catastrophic engine failure. Some later cars were also fitted with the 4.1 liter Buick-derived V6, which was a reliable enough engine, but was not designed for fitment to “full size” cars, and performance was lacking.
Speaking of performance, the Wikipedia article gives performance figures for each engine. Between 1980 and 1985, the most power offered in any Seville was 145 hp. That came from a 6.0L V8. The HT8 HT4100 put out 125-135 hp, the 4.1L Buick V6 put out 125 hp, and the lowly diesel put out a measly 105 hp. It seems odd to read such lowly figures for such an expensive car. But this was only a few years removed from the oil crisis of the 1970s. With stringent CAFE standards, horsepower wasn’t allowed to thrive as it had in the late 1960’s muscle cars.
What prompted me to use this 1985 Cadillac Seville as Mystery Car 123 was seeing one parked near my home. When I was in my early teens, this was one of the cars that caught my fancy. There was something about the “bustle back” that caught my attention. It was different and looked good at the time. Time hasn’t helped to improve the look, but at the time, I really liked the car. And, in my opinion, the Seville looks pretty good in this video. To each his own.
1 “Cadillac Seville” by Wikipedia
2 Comment under 1985 Cadillac Seville “Bustle Back”?
3 Engine advertisement from Curbside Classic: 1980-1985 Cadillac Seville – GM’s Deadly Sin No. 17 – From Halo To Devil’s Pitchfork