So I'm looking into buying a new generation Mustang, and last week I test drove one that is everything I want: silver, v6, manual coupe with low miles. Everything is perfect, except that when I drove it, it omitted a strange and unpleasant noise coming from the transmission that I hadn't heard in any of the Mustangs I drove before. However, this was the first Mustang I drove that had a manual transmission. It also has an AirRaid cold air intake. The owner says it has never been in an accident of any kind and does have a clean title. Is this a common problem in new generation mustangs or is it possible that it's making the noise because of the CAI? It kind of sounds like the engine is revving up while I'm breaking and when I don't even have my foot on the gas at all. Can anyone help?

 

if the engine revs when your foot isnt on the gas, most likely the Idle Air Controller