Cheap Fix: Throttle Cntrl Motor
2004 IS300-Check engine light was on and gave a code that the Throttle Control Motor wouldn't move. Mechanic told me it needed replacing and was a Lexus Dealer only part. I removed the air intake hose and shined a light in the air intake. The butterfly (round, silver, 4" metal disk) had gunk around the edges that was preventing it from opening. I sprayed carberator cleaner around the edges and pressed on the top of it with a large screw driver to open. I worked the butterfly a couple of times while spraying it with the cleaner. Then removed the positive terminal of the battery for a couple of minutes to reset the computer and replaced. Replaced the air intake hose and restarted the engine. Took a little longer to start than normal because of the carb cleaner but when it did, the check engine light was off.