I have a High Idle issue too after my TB port. I can't find it out. Checked vac lines 10x. Changed out my IAC to a new one, no fix. Another new gasket on TB with RTV on both sides. I also have this issue now when I begin to slow down to approach my house, I shut the A/C off and the car begins to accelerate on its own till about 2500-3000 rpms, kinda scarey. Has happened 5 times now.
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2002