Back when turbochargers became common on passenger cars, there was even advice to be sure you let the engine idle for a minute or two before shutting it off, so that the turbocharger could cool. Otherwise the oil in the turbocharger would get baked into a goo. Modern synthetic oils, and turbochargers, handle this better today but I still like to give any hot spots a chance to cool off.

Yes, it was common to install a "turbo timer" that would leave the engine running at idle for a time after you shut off the ignition to let your turbo cool. I drive a 2024 factory turboed vehicle and it still recommends idling for 30 seconds to 2 minutes after parking before shutting the vehicle off and it continues running an electric cooling fan on a timer after you shut off the ignition.

The same set of challenges still exist in 2026 as did in 1986 for a turbo, for the most part.