If the issue is now only from cold then I would suspect the coolant temperature sensor. It's on the inlet manifold behind the stat housing, larger of the two sensors with the multiplug on it. This signals the coolant temperature to the ECU. When cold, the idle speed is increased via the ISCV and the injector pulse is lengthened to enrich the mixture. If the sensor thinks the engine is already hot then it won't trigger this cold start sequence.