what would most likely cause (intermittent,not all the time) fast idle at stop light..thks
used car bought from car dealer near St.Louis,Mo.the car has 120K miles on it.don't know if previous owner followed maintenance schedule.
Vacuum leak is most common cause of high idle, if your IAC (Idle Air Control) valve is clean and working. You won't notice at speed because of the high flow of air in to intake. If your CEL is on an OBDII scan is called for here
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