I dont know if this is normal, but here goes(01 S80 t6) ...

At the initial start up, the car's rpm's fluctuate for like 10 seconds (it bobbles, coughes, and vibrates decent amount), In my dads car-fresh start up none of that fluctuating(he has a nissan altima 05). Also i usually wait till the engine heat meter comes up to the first bar and i start to drive it, even with slow acceleration it will not be able to slowly accelerate smoothly, it will sorta surge then come back down, and im just steadily and slowly accelerating.

Also I hear a loud whistling sound. This is at the first bar of the engine heat meter. when it gets half way(the engine's heat meter) it accelerates normal, and the whistling sound is gone.

Are these normal things from this car?

 

I have the same exact problem, I also have a check engine light, and the code is for running rich in one of the banks. I believe it must be a coolant temp sensor, and plan on looking at it tommorow. Does anyone know where the sensor is located, and is there any test that can be preformed with a multimeter, to see if it is faulty?

TIA

 

Could be a faulty coolant temp sensor.
On some of the cars the sensor and thermostat are located by the Upper Radiator hose.
On the others it is located on the front of the engine under the timing cover.

It could also be many other things.

 

all that goes away when the car fully warms up, that could still be a faulty coolant sensor? Shouldnt the car give me like a Check engine light? What are some of the other things it could be?

 

Yes could still be a coolant temp sensor and not throw codes.

Bad fuel pump (Bleeds back when sitting for a while)

ETM problems.

 

could we cross of etm, since mine was done under warranty, or it could still be the etm?-done like 2 months ago.

 

OK Cross it off.