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The issue started a few months ago where my 997 was having cold misfires. The engine light would come on and the reading was multiple misfires. Otherwise, the car ran fine. I then changed the coils, plugs, air filter, temp sensor, battery, MAF sensor and solenoid valve adjusters. The cold start misfires would not go away. Finally, I had the car boroscoped and the Porsche dealer did not find anything wrong with the engine. After 12 hours of diagnostics at Porsche dealer, it came down to the clutch or reprograming the DME and losing the Softronic flashing. I decided to go with reprograming the DME which was the less expensive option. Since reprograming the DME, the car has not had any cold misfires. No one has ever touched the DME since the Softronic software flashing. According to the Porsche dealer, the software was corrupted.

In hindsight, it would have been easy for me to have the DME flashed back to Porsche default, however I did not realise that the software could get corrupted. Hopefully my experience will help someone else in the future.