When I start the car in morning and put it into gear the car shakes but the moment that it is warmed up even alittle it goes away?? No check engine light,
I also have the same issue. I always let the car warm up for 1-2 mins (until the revs drop) and then the jerkiness/ shuddering in gear is not present. I haven’t really worried about it but I’m interested in others’ opinions.
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On average, even a well serviced 5.2 will run a bit rough when cold. This is in part due to the fact that the 02 sensors are not online giving a signal to the ECU to help sort out the proper AFR. The end result to the 02s being off line is your car will be tracking on a pre set injection phase and depending on your LTFT settings. This will cause noticeable combustion instability
The colder the temps, the worse this rough running condition can be. One of the many reasons is, the SAI system turns on and further creates combustion instability during warm up. As the SAI system is trying to help warm up the cats for the quickest emissions ready car.
A trick you can try is, to start the car. After 3 seconds, put the car in R then back in P to see if that will stop the SAI system. Another way to help is, to NOT let the car sit and “warm up” while many have been left with the idea letting the car sit idle to warm up is best for the car. This is in fact incorrect. Starting the car and driving it ASAP while under low loads and low speeds is best. This actually helps the motor warm up better and faster.
While those two tricks will help they are not going to help if you don’t have good injectors / small vac leaks / other compromised components on the intake track from the intake it self to the PCV system.
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Same here but, when I was high in the rev range the other day my check engine light flashed and then went away and I didn’t if it was related
My s6 is pretty well sorted and has this symptom also. I take CV’s advice and typically dont let it warm up. Start up and go
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Hi rev range misfires trigger the flashing CEL.
If it’s on a cold motor I would still check the date on the coil packs but also be very aware that these motors need either serviced injectors or new replacement injectors. I lean down the serviced path as the flow sheet data gives a good piece of mind.
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Agreed, but it’s not at all fun to drive out our very short driveway before idle is under 800rpm (1-2min.)… trans. hooks hard between 800-1000 
Yeah, I always assumed that it would be worse?
Your user manual actually says right it in. DO NOT LET THE CAR SIT AND IDLE on cold start. It says start the car and within 3 seconds place the car into gear and start driving keeping the load and rpm below I think 3k
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Huh, well Ill start doing that then,