Indeed, I have a picture of the valve that I replaced:

http://i186.photobucket.com/albums/x308/cody_abroad/IACVALVE_zps26370ec6.jpg

Yes, the car has an electric throttle body.

I think the problem must be with the wiring somewhere. The only question is where should I start? At the ECU, or in the ...

So, do I have a bad ECU (computer)?

My car has been throwing a P0505 code since I bought it. This is the air idle control valve fault code. I replaced the air idle control valve, reset the codes, and the car still throws the code telling me my brand new air idle control valve is bad. I've ...

Trying to track down what is causing my 2000 S70 to get 12-14mpg. Have replaced O2 sensors, fuel filter, all basic tune up items, vacuum hoses, etc etc.

Anyhow, when I turn the ignition to ACC, the fuel pressure (I am using a gauge tapped into the fuel rail) jumps to about 45. Almost immediately it ...

Well, I took AACV off and gave it a good cleaning. Reset the fault codes, put it back on. Started the car and the code is still there, instantly. Car idles perfectly.

While I was in there, I checked the throttle body, and it was spotless.

I am using a cheapo scanner, nothing high-tech.

I guess ...

I'd say it's a bit unfounded to say that a leaky evap system wouldn't affect performance. From my experience, leaking air, or changes in fuel pressure can affect performance and gas mileage.

I wiped all of the codes, and then with the car shut off, I unplugged the AACV sensor. I then started the car. The code came back. I guess this means there is a wiring problem somewhere? If I unplug this sensor, and the PCM still throws the 0505 code, it has to be a problem with communication ...

I've got a 2000 S70 base, Denso everything, non-turbo. This is a recurring DTC code that my car is throwing:

P0505 ECM-6207 Air assisted control valve (AACV) Flow too low

Here's the thing; the car idles perfectly and never fluctuates or dips. No idle problems whatsoever. What are the chances of ...

UPDATE: I've replaced my EVAP Vapor Canister Purge Valve (9470775). Cleared all the codes. Have cleared codes and driven the car several times, still getting this P0443 code. I checked the connector, and it is good, clips into place, no corrosion. What gives?

I've searched and searched and ...

Ive got a new knock sensor ready to go. Ive never removed the intake manifold on this car, so I am reading up on it as much as possible before attempting the knock sensor replacement.

NOVEMBER 19, 2013 UPDATE:

Hi fellow Volvo friends and enthusiasts. Are you like me? Do you like a good mystery? If you like good mysteries, then you are really going to like this one:

After several tanks of gas, the car is back to getting lower MPG. All in all, it's averaging 15.89mpg (14.8L/100km ...