High and fluctuating idle Tried. Some learn codes but did not work.
My car has 140000 miles.
My car has an automatic transmission.
Hi - the problem you describe could be a leak in the air intake system (loose hose or fitting), or a problem with the idle air control valve. Are any problem codes set (Check Engine Light on)? If so, these would be instructive in solving this problem. The "idle re-learn" process, essential when replacing throttle position sensors, will not be effective (as you note) when there is an air leak that is "uncontrolled".
I would recommend having an inspection to determine why the idle speed is high completed by a mobile, professional mechanic, such as one from YourMechanic, to diagnose the problem.
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