Sloooo4esT

think it read 90C with car on.

20VT90q

It said the readout should be slightly above ambient with the engine at idle. How is the car running? I'd imagine its probably limiting boost/ignition with those kinds of numbers?

If not its either the sensor or a short (duh). It says to resistance check the sensor at room temperature 20C (68F). You should get a reading of 450-650 ohms. If not, replace sensor and look for shorts if that doesn't do it. Do you have a Urs4 or Urs6? I ask because I think the Urs4 has a connector for the sensor and the urs6 does not. My S2 wiring harness doesn't have a connector for the IAT. This means you need pull back the boot on doing a resistance check and then cut/solder on a new IAT if it needs to be replaced. Stupid Audi.

From SJM:
"Air Temp Sensor

The air temp sensor that the ECU monitors to regulate boost and ignition timing can have poor external connections or can have intermittent connections on the small thermistor at the tip of the sensor. This sensor is located in the intake manifold near the throttle valve.

The wire terminals are normally soldered or spot welded to the air temp sensor. Factory replacement air temp sensors use a separate connector with gold plated terminals instead of the soldered/welded terminals on the original sensor."

Sloooo4esT

gas mileage down to 15mpg, 00561 on scan tool for potential MAF being bad, o2 sensor is white, this is odd to me that I appear to be running lean but using so much fuel.

boost builds smooth, but car does not accel smooth,power comes in stages, 4500 rpm gets most exciting all of a sudden. I have been fighting this for well over a year and have ignored the 00561 code for 2 years, time to bite the bullit eh, but the mpg drop just started in september slowly dropping 2mpgs per tank

get both sensors?

thanks