Rather than just blindly selecting carb heat HOT, I was always told "change air supply" In other words if you had heat selected when the engine failed go to cold ... and vice versa. This works on the principal that something might be blocking the air inlet. If when you change nothing drastic hapens then yes ... go to HOT.
It's funny but with an instructor or examiner next to me PFL's seem a fuddled mess. When I had one for real at 1000' in the Veep everything seemed so relaxed .... I know that sounds rediculous but it's true, it did
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