Originally Posted by SCMomentum
Just read a customer review on another site who discussed his diesel going into "protection mode" during starts in cold weather. Any words of wisdom on this would be greatly appreciated. Thanks.
Modern cars have several modes. There's the Limp mode
that a lot of cars these days have to protect the engine against abuse. People associate the "Limp Mode" with some semi-catastrophic engine or transmission failure which allows you to crawl the car home or to a mechanic at reduced speeds or with limited functionality.
The Protected Mode
is another flavor of the car's self preservation mode. I do not know it specifically for the diesel, but on many cars, you will not be allowed to rev to red line until the engine is fully warmed, the automatic transmission might hold lower gears longer, in winter the heater - when placed in automatic mode will not blow any air for several minutes - until the engine is hot enough: e.g. my Subaru Legacy STI doesn't blow warm air inside the cabin, in winter, until the engine coolant temperature reaches 60 degrees Celsius (140 F) and that is already warm enough.