Im having the exact issue you have minus alot of smoke on heavy acceleration. My maintenance records from PO show that the glowpolugs and injectors were replaced and rebuilt within the last 12 months. However, I have noticed a few items so far that he had paper work for, but were definetely never done to the car.
Oddly the car starts better at 20degrees than 40. It always fires instantly, but smokes alot and shakes and studders. Im going to try the purple wire afterglow trick tommorow, and will be follwing this thread closely.

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