I have a 93 es300 that will not idle when cold. I have meticulously cleaned the IAC valve and it operates smoothly. If the valve is inserted back onto the throttle body in the open position, the car idles immediately upon startup and will be fine until it is shut off again. The service manual states there should be a clicking noise upon shutoff from the IAC valve and I can hear this from a hose that I put on it and to my ear for clarity. When I pull the IAC valve off again, it is in the closed position. I got a replacement from a salvage yard, it came off of the old engine in the open position and that is how I installed it. The engine fired right up, but after shutting it off again, it failed to start without help from the accelerator. When I took it off, it was in the closed position. I haven't put battery power to the connector terminals to see the valve operate, but it seems too much of a coincident that the two act alike. I feel the engine is starving for air but I don't know how to diagnose it. I don't have money to throw at all the possibilities. When the temp gauge moves up, the car starts and idles fine. It's frustrating to only see iac cleaning advice and not much else for my situation. Hoses are mostly new and all seem good. No CEL. Any suggestions would be greatly appreciated.