[norustscott]

I disagree. True, it does not have any direct mixture control function, it simply allows for a faster idle at start up regardless of the ambiant temperature. The 12v power supply to the AAR coil and the radiant heat from the engine case cause it to close at a variable rate depending on the ambient air temperature. I figure it has to reach about 130 or degrees F, or better, before it closes and shuts off air. This is hot enough to always start "open" in North America. However, It does affect mixure ... If it is cold enough to require the cold start injector to fire, and you do not have the additional air from the AAR to bump the RPM, you are going to have a "richer" mixture during the warm up. Albeit not detrimental if the engine is properly tuned and has the correct FI components.