2003 Pontiac Sunfire OBD2 codes P0300, Poi71, and C1275. Flashing engine light

Question

Car starts and idles rough. transmission shift points affected and no power.

Answer 1

P0300 Random misfire

P0171 Fuel trim lean

C1275 EBCM (electrical brake control moduel) is disable until DTC is in history

This is a random misfire, especially when the CK ENG LT flashes, what can cause this are low fuel pressure, or  vacuum leaks creating false air, the fuel pressure specification are 50-60 psi with key on engine off.