No aftermarket headunit will retain the existing mic. But there is a slight work around to getting it to work. You have to cut the microphone jack and splice it into the main harness. What stereo did your car come with? I might be able to help you out.Is there a good aftermarket head unit that will use the existing bluetooth mic for telephone calls? I have installed head units in previous vehicles, and the bluetooth for calls sucks... Thanks in advance!