engine races all the time
No check engine light? What year is it? Anything different happen before then after this problem? I suspect a vacuum leak, but devices being driven by the vacuum could be affected too--believe you've got a throttle-body injection system and has an amient air sensor which may or may not be working properly...see in the old days we used to have a thermal spring heat-riser that jacked up the idle speed with a cam while opening the butterfly valve, now with your TBI there needs to be a semblance of this function is done with an ambient air temperature sensor to make the decision combined with the coolant temperature is able to decide what the enrichment and throttle position should be in....so what I'm saying is it is out of our hands and need to make sure the computer is getting proper instructions from the sensors---~
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