So, when you start your car from cold start, would it idle for about 3 seconds at about 2000 rpm, then drop to 1500, and slowly reduce to 800 as car warms up? That is normal. And then runs and idles at 800 rpm, even when warm? The high idle only happens when you re-start again when car is warm? Have you checked your TPS (throttle position sensor) and ISC (idle speed control)? Check out The KickFix Repair Pages, for Sidekicks and Trackers for the DVM tests on these. Any vacuum leaks?
Please post the year, model, and specs of the car that you are driving (or better yet, put them in your profile so we don't have to try to hunt around to know what car you're driving). In the meantime, generally, when you start your car, 2 things happen. First it idles 'very' high for about 3 seconds or so, then drops down to 'medium' high idle. Does your car do that? This is governed by the dashpot. Afterward, your car remains idling 'medium' high and slowly drops to normal idle as the car warms up. This is governed by ISC. While waiting for specs on your car, you can do simple ISC test, by having car warmed up, idling, then putting the headlights and fan blower on. Does the idle change (drop down? stay the same?) It should not drop down, otherwise ISC is not working properly. Anyway, post your specs, and better answers will come.
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