During some starts (in morning after not driving for several hours), the engine will have a pulsing idle ~750-1000 rpm. after letting it sit for a minute to warm up, i drive down the road. if i am able to drive without stopping, there will be no issues. however, if i come to a stop within 0.5 miles or so, the engine will shut off. when i try and restart, the engine will stall repeatedly. the engine will eventually restart. there have been no codes produced nor any lights on the dash board. has happened several times.
Purchased new chevy colorado 4x4 extended cab with 3.6-liter v6, transmission 8-speed model 8l45. transmission developed shudder during light throttle acceleration between 30 and 70 mph. shudder is cyclic lasting 4 - 12 seconds, reaccurring 45 - 90 seconds. shudder feels similiar to driving over mild rumble strips or rough pavement. first notice transmission problem around 1200 mile mark, total mileage on vehice as of april 11, 2019 is 2750 miles. more information can be found with ge service information (si) as a techinical service bulletin (tsb). refer to these gm tsb's 16-na-175, 18-na-177, and 18-na-355.