Rough Idling, start-up early morning, until engine heats-up

Probable head gasket failure

Very unlikely that it would be a computer problem, it does not control the A/C, or temp gauge. Sounds like multiple problems. A/C could be just low on Freon, if pressure is low, it will not turn on. Temp gauge and rough idle may be related, if temp sensor is bad, the computer wont know the engine temperature and thus not mix the fuel correctly. But there are many things that can cause rough cold engine idle, like dirty throttle plate, or bad idle air control valve. You did not say what engine you have, so this is just general information.

If the thermostat is bad (i.e. stuck open at all times), this would allow coolant to circulate in the engine even when it is below the desired operating temperature. This leads to OVERcooling of the engine. You can either replace the thermostat as a first step or remove it and test it -- closed when cold, open when heated above 190-200F.

try your ful injecton you mite have a injector clogged up try seafome it mite work cant hert to try

the problem if from the map sensor.. when you change it it will run rough and keep cutting off,, keep stating it back and reeving over and over as soon as it cuts off again keep repeating until the CPU gets calibrated with the new sensor and it starts idling smoothly..

Possible vacuum leak and or internal engine issue, have a cyl compression check done along with cyl leakage test

Hello! Most probable cause is a leak in the vacuum line or broken elbow connection to the Positive Crankcase Ventilation (PCV) valve...Check PCV and its vacuum line...Send results...

Guru..............saailer

I’m happy to help further over the phone at https://www.6ya.com/expert/david_6df67de3b14de867

YOUR CAR HAS AN ABS SENSOR ON EACH WHEEL! YOU SHOULD HAVE THE CODE READ SO U KNOW WHERE TO START.MAY SAVE YOURSELF SOME MONEY.ROUGH IDLE W/HEAT ON.CHECK THE VACUUM LINES GOING THROUGH THE FIREWALL.WHEN U HAVE THE HEATER ON THE VENTS RUN OFF ENGINE VACUUM.LOW ENGINE VACUUM=ROUGH IDLE.G.M. NEEDS A 100K WARRANTY.THERE STUFF KEEPS THE AUTOMOTIVE REPAIR SHOPS VERY BUSY.

does it have a cold start injector seperate from the other injectors usually on the upper intake somewhere with a fuel line going to it