My coupe is running really nicely. Except, first thing in the morning. Starting from cold I have to sit there with it, keeping it over 1000rpm until the temperature needle starts to rise. If I don't do that it stalls and won't restart for several hours.

My mechanic says dirty injector. I have been putting tons of injector cleaner in the gas. And, this started one day out of the blue.

Any guesses or ways I proceed?