My S5 is going from 1000 to 1300 up and down , I have changed the tps and checked it with the light method, Checked for vac leaks etc... Could it be the Air Flow Meter? When I check the resistance on the AFM it is not smooth on the multimeter it goes high and low in a few spots. Dont know if this is normal or not, The service manual only checks resistance closed then open, No mention of meauring it through the travel but it looks logical that it should not spike, I would think the resistance change would look like a smooth change
Anyone Had any AFM S5 problems like this Help

 

I had a problem like this. It turned out to be a vac leaks though. I sprayed break cleaner on all the visible vacuum lines and it didn't change idle at all. Then I pulled up the UIM and replaced all the vac tubing, injector O Rings, and soft gaskets. The leaks were really tiny and very well hidden. Not a problem after that.

 

Try this. Warm the car up and turn off the engine. Short the initial set connector and then crank the engine again. Now try setting the idle speed by turning the adjust screw on top of the Throttle Body. If the idle speed changes, then set it to 750 RPM. If turning the screw does not change the idle, then you've probably got a vacuum leak. They can be tough to find.

 

+1 on vac leak

 

Iwas checking the resistance of my S5 AFM and it is the same as yours. Although I have a code #8.

 

check your tps and air leaks

 

I have had some time to play around looking and replaceing hoses trying to find a vac problem. No luck yet on the hoses but I did find out that I could push on the snorkle pipe going to the throttle boby and the problem would leave. I have checked the snorkile pipe and found no cracks or leaks even to the bac or the rapid warm up valve hoses. But I removed the throttle body checked the connections. it appears that the spacer has some leaky issues or at least I hope so it looked as if it had a hard previous life. Going to replace it as soon as it arrives. I just hope it works.