What is iac
Idle air control valve.
http://www.thecorsa.co.uk/mechanical-tutorials/362-how-clean-idle- control-valve.html -- check this out. You may find it very helpful.
Its like a sensor that tells the engine how much air is to be pumped into the cylinders when u gas the pedal. Faulty ones can result in improper idiling and irratic accelarations
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