I must say, I have never seen this type of failure. I wouldn't have sweated that resistance reading. Good catch!

My guess is the spring is for adapting this IAC valve to different motors who require different idle airflow rates. This way, you can reuse your valve and it won't be operating within 10% of its duty cycle range on some motors.

 

I just noticed that I can actually acell and decell smoothly now. I didn't even realize my car was supposed to do that. It has been such a long time since my IAC has worked properly. I guess it's been going out of specs for a long time. Now I put a little bit of gas on and the car does the rest, slowly opening the IAC.

Add that to the list of problems

car feels like it's acelerating or decellerating,

 

I didn't quite follow that one. When you crack the throttle open, the ECU should park the idle air valve, as it isn't needed anymore. When you coast to a stop with the engine in gear, the ECU should go into fuel cut, which is dictated by the TPS and has nothing to do with the IAC until below ~1500 RPM.

 

It seems like my idle air controller adjusts constantly while I drive now to give me a smoother ride, then when I release the pedal it slowly closes allowing my car to coast. Before I'd let off the gas and it would decellerate hard. Now it floats nicely.

I've never looked at how it operates before, but It seems that when you put on the gas, the IAC opens slowly, then when you let off the gas, it brings it back down to idle.